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