src/hb-unicode.cc

   1 /*
   2  * Copyright © 2009  Red Hat, Inc.
   3  * Copyright © 2011 Codethink Limited
   4  * Copyright © 2010,2011  Google, Inc.
   5  *
   6  *  This is part of HarfBuzz, a text shaping library.
   7  *
   8  * Permission is hereby granted, without written agreement and without
   9  * license or royalty fees, to use, copy, modify, and distribute this
  10  * software and its documentation for any purpose, provided that the
  11  * above copyright notice and the following two paragraphs appear in
  12  * all copies of this software.
  13  *
  14  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  15  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  16  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  17  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  18  * DAMAGE.
  19  *
  20  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  21  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  22  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  23  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  24  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  25  *
  26  * Red Hat Author(s): Behdad Esfahbod
  27  * Codethink Author(s): Ryan Lortie
  28  * Google Author(s): Behdad Esfahbod
  29  */
  30
  31 #include "hb-private.hh"
  32
  33 #include "hb-unicode-private.hh"
  34
  35 HB_BEGIN_DECLS
  36
  37
  38 /*
  39  * hb_unicode_funcs_t
  40  */
  41
  42 static unsigned int
  43 hb_unicode_combining_class_nil (hb_unicode_funcs_t *ufuncs    HB_UNUSED,
  44                                 hb_codepoint_t      unicode   HB_UNUSED,
  45                                 void               *user_data HB_UNUSED)
  46 {
  47   return 0;
  48 }
  49
  50 static unsigned int
  51 hb_unicode_eastasian_width_nil (hb_unicode_funcs_t *ufuncs    HB_UNUSED,
  52                                 hb_codepoint_t      unicode   HB_UNUSED,
  53                                 void               *user_data HB_UNUSED)
  54 {
  55   return 1;
  56 }
  57
  58 static hb_unicode_general_category_t
  59 hb_unicode_general_category_nil (hb_unicode_funcs_t *ufuncs    HB_UNUSED,
  60                                  hb_codepoint_t      unicode   HB_UNUSED,
  61                                  void               *user_data HB_UNUSED)
  62 {
  63   return HB_UNICODE_GENERAL_CATEGORY_OTHER_LETTER;
  64 }
  65
  66 static hb_codepoint_t
  67 hb_unicode_mirroring_nil (hb_unicode_funcs_t *ufuncs    HB_UNUSED,
  68                           hb_codepoint_t      unicode   HB_UNUSED,
  69                           void               *user_data HB_UNUSED)
  70 {
  71   return unicode;
  72 }
  73
  74 static hb_script_t
  75 hb_unicode_script_nil (hb_unicode_funcs_t *ufuncs    HB_UNUSED,
  76                        hb_codepoint_t      unicode   HB_UNUSED,
  77                        void               *user_data HB_UNUSED)
  78 {
  79   return HB_SCRIPT_UNKNOWN;
  80 }
  81
  82 static hb_bool_t
  83 hb_unicode_compose_nil (hb_unicode_funcs_t *ufuncs    HB_UNUSED,
  84                         hb_codepoint_t      a         HB_UNUSED,
  85                         hb_codepoint_t      b         HB_UNUSED,
  86                         hb_codepoint_t     *ab        HB_UNUSED,
  87                         void               *user_data HB_UNUSED)
  88 {
  89   /* TODO handle Hangul jamo here? */
  90   return FALSE;
  91 }
  92
  93 static hb_bool_t
  94 hb_unicode_decompose_nil (hb_unicode_funcs_t *ufuncs    HB_UNUSED,
  95                           hb_codepoint_t      ab        HB_UNUSED,
  96                           hb_codepoint_t     *a         HB_UNUSED,
  97                           hb_codepoint_t     *b         HB_UNUSED,
  98                           void               *user_data HB_UNUSED)
  99 {
 100   /* TODO handle Hangul jamo here? */
 101   return FALSE;
 102 }
 103
 104
 105 hb_unicode_funcs_t _hb_unicode_funcs_nil = {
 106   HB_OBJECT_HEADER_STATIC,
 107
 108   NULL, /* parent */
 109   TRUE, /* immutable */
 110   {
 111 #define HB_UNICODE_FUNC_IMPLEMENT(name) hb_unicode_##name##_nil,
 112     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
 113 #undef HB_UNICODE_FUNC_IMPLEMENT
 114   }
 115 };
 116
 117
 118 hb_unicode_funcs_t *
 119 hb_unicode_funcs_get_default (void)
 120 {
 121   return &_hb_unicode_funcs_default;
 122 }
 123
 124 hb_unicode_funcs_t *
 125 hb_unicode_funcs_create (hb_unicode_funcs_t *parent)
 126 {
 127   hb_unicode_funcs_t *ufuncs;
 128
 129   if (!(ufuncs = hb_object_create<hb_unicode_funcs_t> ()))
 130     return &_hb_unicode_funcs_nil;
 131
 132   if (!parent)
 133     parent = &_hb_unicode_funcs_nil;
 134
 135   hb_unicode_funcs_make_immutable (parent);
 136   ufuncs->parent = hb_unicode_funcs_reference (parent);
 137
 138   ufuncs->func = parent->func;
 139
 140   /* We can safely copy user_data from parent since we hold a reference
 141    * onto it and it's immutable.  We should not copy the destroy notifiers
 142    * though. */
 143   ufuncs->user_data = parent->user_data;
 144
 145   return ufuncs;
 146 }
 147
 148 hb_unicode_funcs_t *
 149 hb_unicode_funcs_get_empty (void)
 150 {
 151   return &_hb_unicode_funcs_nil;
 152 }
 153
 154 hb_unicode_funcs_t *
 155 hb_unicode_funcs_reference (hb_unicode_funcs_t *ufuncs)
 156 {
 157   return hb_object_reference (ufuncs);
 158 }
 159
 160 void
 161 hb_unicode_funcs_destroy (hb_unicode_funcs_t *ufuncs)
 162 {
 163   if (!hb_object_destroy (ufuncs)) return;
 164
 165 #define HB_UNICODE_FUNC_IMPLEMENT(name) \
 166   if (ufuncs->destroy.name) ufuncs->destroy.name (ufuncs->user_data.name);
 167     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
 168 #undef HB_UNICODE_FUNC_IMPLEMENT
 169
 170   hb_unicode_funcs_destroy (ufuncs->parent);
 171
 172   free (ufuncs);
 173 }
 174
 175 hb_bool_t
 176 hb_unicode_funcs_set_user_data (hb_unicode_funcs_t *ufuncs,
 177                                 hb_user_data_key_t *key,
 178                                 void *              data,
 179                                 hb_destroy_func_t   destroy)
 180 {
 181   return hb_object_set_user_data (ufuncs, key, data, destroy);
 182 }
 183
 184 void *
 185 hb_unicode_funcs_get_user_data (hb_unicode_funcs_t *ufuncs,
 186                                 hb_user_data_key_t *key)
 187 {
 188   return hb_object_get_user_data (ufuncs, key);
 189 }
 190
 191
 192 void
 193 hb_unicode_funcs_make_immutable (hb_unicode_funcs_t *ufuncs)
 194 {
 195   if (hb_object_is_inert (ufuncs))
 196     return;
 197
 198   ufuncs->immutable = TRUE;
 199 }
 200
 201 hb_bool_t
 202 hb_unicode_funcs_is_immutable (hb_unicode_funcs_t *ufuncs)
 203 {
 204   return ufuncs->immutable;
 205 }
 206
 207 hb_unicode_funcs_t *
 208 hb_unicode_funcs_get_parent (hb_unicode_funcs_t *ufuncs)
 209 {
 210   return ufuncs->parent ? ufuncs->parent : &_hb_unicode_funcs_nil;
 211 }
 212
 213
 214 #define HB_UNICODE_FUNC_IMPLEMENT(name)                                         \
 215                                                                                 \
 216 void                                                                            \
 217 hb_unicode_funcs_set_##name##_func (hb_unicode_funcs_t             *ufuncs,     \
 218                                     hb_unicode_##name##_func_t      func,       \
 219                                     void                           *user_data,  \
 220                                     hb_destroy_func_t               destroy)    \
 221 {                                                                               \
 222   if (ufuncs->immutable)                                                        \
 223     return;                                                                     \
 224                                                                                 \
 225   if (ufuncs->destroy.name)                                                     \
 226     ufuncs->destroy.name (ufuncs->user_data.name);                              \
 227                                                                                 \
 228   if (func) {                                                                   \
 229     ufuncs->func.name = func;                                                   \
 230     ufuncs->user_data.name = user_data;                                         \
 231     ufuncs->destroy.name = destroy;                                             \
 232   } else {                                                                      \
 233     ufuncs->func.name = ufuncs->parent->func.name;                              \
 234     ufuncs->user_data.name = ufuncs->parent->user_data.name;                    \
 235     ufuncs->destroy.name = NULL;                                                \
 236   }                                                                             \
 237 }
 238
 239     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
 240 #undef HB_UNICODE_FUNC_IMPLEMENT
 241
 242
 243 #define HB_UNICODE_FUNC_IMPLEMENT(return_type, name)                            \
 244                                                                                 \
 245 return_type                                                                     \
 246 hb_unicode_##name (hb_unicode_funcs_t *ufuncs,                                  \
 247                    hb_codepoint_t      unicode)                                 \
 248 {                                                                               \
 249   return ufuncs->func.name (ufuncs, unicode, ufuncs->user_data.name);           \
 250 }
 251     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS_SIMPLE
 252 #undef HB_UNICODE_FUNC_IMPLEMENT
 253
 254 hb_bool_t
 255 hb_unicode_compose (hb_unicode_funcs_t *ufuncs,
 256                     hb_codepoint_t      a,
 257                     hb_codepoint_t      b,
 258                     hb_codepoint_t     *ab)
 259 {
 260   *ab = 0;
 261   return ufuncs->func.compose (ufuncs, a, b, ab, ufuncs->user_data.compose);
 262 }
 263
 264 hb_bool_t
 265 hb_unicode_decompose (hb_unicode_funcs_t *ufuncs,
 266                       hb_codepoint_t      ab,
 267                       hb_codepoint_t     *a,
 268                       hb_codepoint_t     *b)
 269 {
 270   *a = *b = 0;
 271   return ufuncs->func.decompose (ufuncs, ab, a, b, ufuncs->user_data.decompose);
 272 }
 273
 274 HB_END_DECLS