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_get_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_get_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_get_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_get_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_get_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
  83 hb_unicode_funcs_t _hb_unicode_funcs_nil = {
  84   HB_OBJECT_HEADER_STATIC,
  85
  86   NULL, /* parent */
  87   TRUE, /* immutable */
  88   {
  89 #define HB_UNICODE_FUNC_IMPLEMENT(name) hb_unicode_get_##name##_nil,
  90     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
  91 #undef HB_UNICODE_FUNC_IMPLEMENT
  92   }
  93 };
  94
  95
  96 hb_unicode_funcs_t *
  97 hb_unicode_funcs_get_default (void)
  98 {
  99   return &_hb_unicode_funcs_default;
 100 }
 101
 102 hb_unicode_funcs_t *
 103 hb_unicode_funcs_create (hb_unicode_funcs_t *parent)
 104 {
 105   hb_unicode_funcs_t *ufuncs;
 106
 107   if (!(ufuncs = hb_object_create<hb_unicode_funcs_t> ()))
 108     return &_hb_unicode_funcs_nil;
 109
 110   if (!parent)
 111     parent = &_hb_unicode_funcs_nil;
 112
 113   hb_unicode_funcs_make_immutable (parent);
 114   ufuncs->parent = hb_unicode_funcs_reference (parent);
 115
 116   ufuncs->get = parent->get;
 117
 118   /* We can safely copy user_data from parent since we hold a reference
 119    * onto it and it's immutable.  We should not copy the destroy notifiers
 120    * though. */
 121   ufuncs->user_data = parent->user_data;
 122
 123   return ufuncs;
 124 }
 125
 126 hb_unicode_funcs_t *
 127 hb_unicode_funcs_get_empty (void)
 128 {
 129   return &_hb_unicode_funcs_nil;
 130 }
 131
 132 hb_unicode_funcs_t *
 133 hb_unicode_funcs_reference (hb_unicode_funcs_t *ufuncs)
 134 {
 135   return hb_object_reference (ufuncs);
 136 }
 137
 138 void
 139 hb_unicode_funcs_destroy (hb_unicode_funcs_t *ufuncs)
 140 {
 141   if (!hb_object_destroy (ufuncs)) return;
 142
 143 #define HB_UNICODE_FUNC_IMPLEMENT(name) \
 144   if (ufuncs->destroy.name) ufuncs->destroy.name (ufuncs->user_data.name);
 145     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
 146 #undef HB_UNICODE_FUNC_IMPLEMENT
 147
 148   hb_unicode_funcs_destroy (ufuncs->parent);
 149
 150   free (ufuncs);
 151 }
 152
 153 hb_bool_t
 154 hb_unicode_funcs_set_user_data (hb_unicode_funcs_t *ufuncs,
 155                                 hb_user_data_key_t *key,
 156                                 void *              data,
 157                                 hb_destroy_func_t   destroy)
 158 {
 159   return hb_object_set_user_data (ufuncs, key, data, destroy);
 160 }
 161
 162 void *
 163 hb_unicode_funcs_get_user_data (hb_unicode_funcs_t *ufuncs,
 164                                 hb_user_data_key_t *key)
 165 {
 166   return hb_object_get_user_data (ufuncs, key);
 167 }
 168
 169
 170 void
 171 hb_unicode_funcs_make_immutable (hb_unicode_funcs_t *ufuncs)
 172 {
 173   if (hb_object_is_inert (ufuncs))
 174     return;
 175
 176   ufuncs->immutable = TRUE;
 177 }
 178
 179 hb_bool_t
 180 hb_unicode_funcs_is_immutable (hb_unicode_funcs_t *ufuncs)
 181 {
 182   return ufuncs->immutable;
 183 }
 184
 185 hb_unicode_funcs_t *
 186 hb_unicode_funcs_get_parent (hb_unicode_funcs_t *ufuncs)
 187 {
 188   return ufuncs->parent ? ufuncs->parent : &_hb_unicode_funcs_nil;
 189 }
 190
 191
 192 #define HB_UNICODE_FUNC_IMPLEMENT(name)                                         \
 193                                                                                 \
 194 void                                                                            \
 195 hb_unicode_funcs_set_##name##_func (hb_unicode_funcs_t             *ufuncs,     \
 196                                     hb_unicode_get_##name##_func_t  func,       \
 197                                     void                           *user_data,  \
 198                                     hb_destroy_func_t               destroy)    \
 199 {                                                                               \
 200   if (ufuncs->immutable)                                                        \
 201     return;                                                                     \
 202                                                                                 \
 203   if (ufuncs->destroy.name)                                                     \
 204     ufuncs->destroy.name (ufuncs->user_data.name);                              \
 205                                                                                 \
 206   if (func) {                                                                   \
 207     ufuncs->get.name = func;                                                    \
 208     ufuncs->user_data.name = user_data;                                         \
 209     ufuncs->destroy.name = destroy;                                             \
 210   } else {                                                                      \
 211     ufuncs->get.name = ufuncs->parent->get.name;                                \
 212     ufuncs->user_data.name = ufuncs->parent->user_data.name;                    \
 213     ufuncs->destroy.name = NULL;                                                \
 214   }                                                                             \
 215 }
 216
 217     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
 218 #undef HB_UNICODE_FUNC_IMPLEMENT
 219
 220
 221 #define HB_UNICODE_FUNC_IMPLEMENT(return_type, name)                            \
 222                                                                                 \
 223 return_type                                                                     \
 224 hb_unicode_get_##name (hb_unicode_funcs_t *ufuncs,                              \
 225                        hb_codepoint_t      unicode)                             \
 226 {                                                                               \
 227   return ufuncs->get.name (ufuncs, unicode, ufuncs->user_data.name);            \
 228 }
 229     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS_SIMPLE
 230 #undef HB_UNICODE_FUNC_IMPLEMENT
 231
 232
 233 HB_END_DECLS