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 #define HB_UNICODE_FUNC_IMPLEMENT(return_type, name, default_value)             \
  43                                                                                 \
  44                                                                                 \
  45 static return_type                                                              \
  46 hb_unicode_get_##name##_nil (hb_unicode_funcs_t *ufuncs    HB_UNUSED,           \
  47                              hb_codepoint_t      unicode   HB_UNUSED,           \
  48                              void               *user_data HB_UNUSED)           \
  49 {                                                                               \
  50   return default_value;                                                         \
  51 }
  52
  53   HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
  54 #undef HB_UNICODE_FUNC_IMPLEMENT
  55
  56
  57 hb_unicode_funcs_t _hb_unicode_funcs_nil = {
  58   HB_OBJECT_HEADER_STATIC,
  59
  60   NULL, /* parent */
  61   TRUE, /* immutable */
  62   {
  63 #define HB_UNICODE_FUNC_IMPLEMENT(return_type, name, default_value) hb_unicode_get_##name##_nil,
  64     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
  65 #undef HB_UNICODE_FUNC_IMPLEMENT
  66   }
  67 };
  68
  69
  70 hb_unicode_funcs_t *
  71 hb_unicode_funcs_get_default (void)
  72 {
  73   return &_hb_unicode_funcs_default;
  74 }
  75
  76 hb_unicode_funcs_t *
  77 hb_unicode_funcs_create (hb_unicode_funcs_t *parent)
  78 {
  79   hb_unicode_funcs_t *ufuncs;
  80
  81   if (!(ufuncs = hb_object_create<hb_unicode_funcs_t> ()))
  82     return &_hb_unicode_funcs_nil;
  83
  84   if (!parent)
  85     parent = &_hb_unicode_funcs_nil;
  86
  87   hb_unicode_funcs_make_immutable (parent);
  88   ufuncs->parent = hb_unicode_funcs_reference (parent);
  89
  90   ufuncs->get = parent->get;
  91
  92   /* We can safely copy user_data from parent since we hold a reference
  93    * onto it and it's immutable.  We should not copy the destroy notifiers
  94    * though. */
  95   ufuncs->user_data = parent->user_data;
  96
  97   return ufuncs;
  98 }
  99
 100 hb_unicode_funcs_t *
 101 hb_unicode_funcs_get_empty (void)
 102 {
 103   return &_hb_unicode_funcs_nil;
 104 }
 105
 106 hb_unicode_funcs_t *
 107 hb_unicode_funcs_reference (hb_unicode_funcs_t *ufuncs)
 108 {
 109   return hb_object_reference (ufuncs);
 110 }
 111
 112 void
 113 hb_unicode_funcs_destroy (hb_unicode_funcs_t *ufuncs)
 114 {
 115   if (!hb_object_destroy (ufuncs)) return;
 116
 117 #define HB_UNICODE_FUNC_IMPLEMENT(return_type, name, default_value) \
 118   if (ufuncs->destroy.name) ufuncs->destroy.name (ufuncs->user_data.name);
 119     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
 120 #undef HB_UNICODE_FUNC_IMPLEMENT
 121
 122   hb_unicode_funcs_destroy (ufuncs->parent);
 123
 124   free (ufuncs);
 125 }
 126
 127 hb_bool_t
 128 hb_unicode_funcs_set_user_data (hb_unicode_funcs_t *ufuncs,
 129                                 hb_user_data_key_t *key,
 130                                 void *              data,
 131                                 hb_destroy_func_t   destroy)
 132 {
 133   return hb_object_set_user_data (ufuncs, key, data, destroy);
 134 }
 135
 136 void *
 137 hb_unicode_funcs_get_user_data (hb_unicode_funcs_t *ufuncs,
 138                                 hb_user_data_key_t *key)
 139 {
 140   return hb_object_get_user_data (ufuncs, key);
 141 }
 142
 143
 144 void
 145 hb_unicode_funcs_make_immutable (hb_unicode_funcs_t *ufuncs)
 146 {
 147   if (hb_object_is_inert (ufuncs))
 148     return;
 149
 150   ufuncs->immutable = TRUE;
 151 }
 152
 153 hb_bool_t
 154 hb_unicode_funcs_is_immutable (hb_unicode_funcs_t *ufuncs)
 155 {
 156   return ufuncs->immutable;
 157 }
 158
 159 hb_unicode_funcs_t *
 160 hb_unicode_funcs_get_parent (hb_unicode_funcs_t *ufuncs)
 161 {
 162   return ufuncs->parent ? ufuncs->parent : &_hb_unicode_funcs_nil;
 163 }
 164
 165
 166 #define HB_UNICODE_FUNC_IMPLEMENT(return_type, name, default_value)             \
 167                                                                                 \
 168 void                                                                            \
 169 hb_unicode_funcs_set_##name##_func (hb_unicode_funcs_t             *ufuncs,     \
 170                                     hb_unicode_get_##name##_func_t  func,       \
 171                                     void                           *user_data,  \
 172                                     hb_destroy_func_t               destroy)    \
 173 {                                                                               \
 174   if (ufuncs->immutable)                                                        \
 175     return;                                                                     \
 176                                                                                 \
 177   if (ufuncs->destroy.name)                                                     \
 178     ufuncs->destroy.name (ufuncs->user_data.name);                              \
 179                                                                                 \
 180   if (func) {                                                                   \
 181     ufuncs->get.name = func;                                                    \
 182     ufuncs->user_data.name = user_data;                                         \
 183     ufuncs->destroy.name = destroy;                                             \
 184   } else {                                                                      \
 185     ufuncs->get.name = ufuncs->parent->get.name;                                \
 186     ufuncs->user_data.name = ufuncs->parent->user_data.name;                    \
 187     ufuncs->destroy.name = NULL;                                                \
 188   }                                                                             \
 189 }                                                                               \
 190                                                                                 \
 191 return_type                                                                     \
 192 hb_unicode_get_##name (hb_unicode_funcs_t *ufuncs,                              \
 193                        hb_codepoint_t      unicode)                             \
 194 {                                                                               \
 195   return ufuncs->get.name (ufuncs, unicode, ufuncs->user_data.name);            \
 196 }
 197
 198     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
 199 #undef HB_UNICODE_FUNC_IMPLEMENT
 200
 201
 202 HB_END_DECLS