src/hb-buffer.h

   1 /*
   2  * Copyright © 1998-2004  David Turner and Werner Lemberg
   3  * Copyright © 2004,2007,2009  Red Hat, Inc.
   4  * Copyright © 2011,2012  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): Owen Taylor, Behdad Esfahbod
  27  * Google Author(s): Behdad Esfahbod
  28  */
  29
  30 #ifndef HB_H_IN
  31 #error "Include <hb.h> instead."
  32 #endif
  33
  34 #ifndef HB_BUFFER_H
  35 #define HB_BUFFER_H
  36
  37 #include "hb-common.h"
  38 #include "hb-unicode.h"
  39 #include "hb-font.h"
  40
  41 HB_BEGIN_DECLS
  42
  43
  44 typedef struct hb_glyph_info_t {
  45   hb_codepoint_t codepoint;
  46   hb_mask_t      mask;
  47   uint32_t       cluster;
  48
  49   /*< private >*/
  50   hb_var_int_t   var1;
  51   hb_var_int_t   var2;
  52 } hb_glyph_info_t;
  53
  54 typedef struct hb_glyph_position_t {
  55   hb_position_t  x_advance;
  56   hb_position_t  y_advance;
  57   hb_position_t  x_offset;
  58   hb_position_t  y_offset;
  59
  60   /*< private >*/
  61   hb_var_int_t   var;
  62 } hb_glyph_position_t;
  63
  64
  65 typedef struct hb_segment_properties_t {
  66   hb_direction_t  direction;
  67   hb_script_t     script;
  68   hb_language_t   language;
  69   /*< private >*/
  70   void           *reserved1;
  71   void           *reserved2;
  72 } hb_segment_properties_t;
  73
  74 #define HB_SEGMENT_PROPERTIES_DEFAULT {HB_DIRECTION_INVALID, \
  75                                        HB_SCRIPT_INVALID, \
  76                                        HB_LANGUAGE_INVALID, \
  77                                        NULL, \
  78                                        NULL}
  79
  80 hb_bool_t
  81 hb_segment_properties_equal (const hb_segment_properties_t *a,
  82                              const hb_segment_properties_t *b);
  83
  84 unsigned int
  85 hb_segment_properties_hash (const hb_segment_properties_t *p);
  86
  87
  88
  89 /*
  90  * hb_buffer_t
  91  */
  92
  93 typedef struct hb_buffer_t hb_buffer_t;
  94
  95 hb_buffer_t *
  96 hb_buffer_create (void);
  97
  98 hb_buffer_t *
  99 hb_buffer_get_empty (void);
 100
 101 hb_buffer_t *
 102 hb_buffer_reference (hb_buffer_t *buffer);
 103
 104 void
 105 hb_buffer_destroy (hb_buffer_t *buffer);
 106
 107 hb_bool_t
 108 hb_buffer_set_user_data (hb_buffer_t        *buffer,
 109                          hb_user_data_key_t *key,
 110                          void *              data,
 111                          hb_destroy_func_t   destroy,
 112                          hb_bool_t           replace);
 113
 114 void *
 115 hb_buffer_get_user_data (hb_buffer_t        *buffer,
 116                          hb_user_data_key_t *key);
 117
 118
 119 typedef enum {
 120   HB_BUFFER_CONTENT_TYPE_INVALID = 0,
 121   HB_BUFFER_CONTENT_TYPE_UNICODE,
 122   HB_BUFFER_CONTENT_TYPE_GLYPHS
 123 } hb_buffer_content_type_t;
 124
 125 void
 126 hb_buffer_set_content_type (hb_buffer_t              *buffer,
 127                             hb_buffer_content_type_t  content_type);
 128
 129 hb_buffer_content_type_t
 130 hb_buffer_get_content_type (hb_buffer_t *buffer);
 131
 132
 133 void
 134 hb_buffer_set_unicode_funcs (hb_buffer_t        *buffer,
 135                              hb_unicode_funcs_t *unicode_funcs);
 136
 137 hb_unicode_funcs_t *
 138 hb_buffer_get_unicode_funcs (hb_buffer_t        *buffer);
 139
 140 void
 141 hb_buffer_set_direction (hb_buffer_t    *buffer,
 142                          hb_direction_t  direction);
 143
 144 hb_direction_t
 145 hb_buffer_get_direction (hb_buffer_t *buffer);
 146
 147 void
 148 hb_buffer_set_script (hb_buffer_t *buffer,
 149                       hb_script_t  script);
 150
 151 hb_script_t
 152 hb_buffer_get_script (hb_buffer_t *buffer);
 153
 154 void
 155 hb_buffer_set_language (hb_buffer_t   *buffer,
 156                         hb_language_t  language);
 157
 158
 159 hb_language_t
 160 hb_buffer_get_language (hb_buffer_t *buffer);
 161
 162 void
 163 hb_buffer_set_segment_properties (hb_buffer_t *buffer,
 164                                   const hb_segment_properties_t *props);
 165
 166 void
 167 hb_buffer_get_segment_properties (hb_buffer_t *buffer,
 168                                   hb_segment_properties_t *props);
 169
 170 void
 171 hb_buffer_guess_segment_properties (hb_buffer_t *buffer);
 172
 173
 174 typedef enum {
 175   HB_BUFFER_FLAGS_DEFAULT                       = 0x00000000,
 176   HB_BUFFER_FLAG_BOT                            = 0x00000001, /* Beginning-of-text */
 177   HB_BUFFER_FLAG_EOT                            = 0x00000002, /* End-of-text */
 178   HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES    = 0x00000004
 179 } hb_buffer_flags_t;
 180
 181 void
 182 hb_buffer_set_flags (hb_buffer_t       *buffer,
 183                      hb_buffer_flags_t  flags);
 184
 185 hb_buffer_flags_t
 186 hb_buffer_get_flags (hb_buffer_t *buffer);
 187
 188
 189 /* Resets the buffer.  Afterwards it's as if it was just created,
 190  * except that it has a larger buffer allocated perhaps... */
 191 void
 192 hb_buffer_reset (hb_buffer_t *buffer);
 193
 194 /* Like reset, but does NOT clear unicode_funcs. */
 195 void
 196 hb_buffer_clear_contents (hb_buffer_t *buffer);
 197
 198 /* Returns false if allocation failed */
 199 hb_bool_t
 200 hb_buffer_pre_allocate (hb_buffer_t  *buffer,
 201                         unsigned int  size);
 202
 203
 204 /* Returns false if allocation has failed before */
 205 hb_bool_t
 206 hb_buffer_allocation_successful (hb_buffer_t  *buffer);
 207
 208 void
 209 hb_buffer_reverse (hb_buffer_t *buffer);
 210
 211 void
 212 hb_buffer_reverse_clusters (hb_buffer_t *buffer);
 213
 214
 215 /* Filling the buffer in */
 216
 217 void
 218 hb_buffer_add (hb_buffer_t    *buffer,
 219                hb_codepoint_t  codepoint,
 220                unsigned int    cluster);
 221
 222 void
 223 hb_buffer_add_utf8 (hb_buffer_t  *buffer,
 224                     const char   *text,
 225                     int           text_length,
 226                     unsigned int  item_offset,
 227                     int           item_length);
 228
 229 void
 230 hb_buffer_add_utf16 (hb_buffer_t    *buffer,
 231                      const uint16_t *text,
 232                      int             text_length,
 233                      unsigned int    item_offset,
 234                      int             item_length);
 235
 236 void
 237 hb_buffer_add_utf32 (hb_buffer_t    *buffer,
 238                      const uint32_t *text,
 239                      int             text_length,
 240                      unsigned int    item_offset,
 241                      int             item_length);
 242
 243
 244 /* Clears any new items added at the end */
 245 hb_bool_t
 246 hb_buffer_set_length (hb_buffer_t  *buffer,
 247                       unsigned int  length);
 248
 249 /* Return value valid as long as buffer not modified */
 250 unsigned int
 251 hb_buffer_get_length (hb_buffer_t *buffer);
 252
 253 /* Getting glyphs out of the buffer */
 254
 255 /* Return value valid as long as buffer not modified */
 256 hb_glyph_info_t *
 257 hb_buffer_get_glyph_infos (hb_buffer_t  *buffer,
 258                            unsigned int *length);
 259
 260 /* Return value valid as long as buffer not modified */
 261 hb_glyph_position_t *
 262 hb_buffer_get_glyph_positions (hb_buffer_t  *buffer,
 263                                unsigned int *length);
 264
 265
 266 /* Reorders a glyph buffer to have canonical in-cluster glyph order / position.
 267  * The resulting clusters should behave identical to pre-reordering clusters.
 268  * NOTE: This has nothing to do with Unicode normalization. */
 269 void
 270 hb_buffer_normalize_glyphs (hb_buffer_t *buffer);
 271
 272
 273 /*
 274  * Serialize
 275  */
 276
 277 typedef enum {
 278   HB_BUFFER_SERIALIZE_FLAGS_DEFAULT             = 0x00000000,
 279   HB_BUFFER_SERIALIZE_FLAG_NO_CLUSTERS          = 0x00000001,
 280   HB_BUFFER_SERIALIZE_FLAG_NO_POSITIONS         = 0x00000002,
 281   HB_BUFFER_SERIALIZE_FLAG_NO_GLYPH_NAMES       = 0x00000004
 282 } hb_buffer_serialize_flags_t;
 283
 284 typedef enum {
 285   HB_BUFFER_SERIALIZE_FORMAT_TEXT       = HB_TAG('T','E','X','T'),
 286   HB_BUFFER_SERIALIZE_FORMAT_JSON       = HB_TAG('J','S','O','N'),
 287   HB_BUFFER_SERIALIZE_FORMAT_INVALID    = HB_TAG_NONE
 288 } hb_buffer_serialize_format_t;
 289
 290 /* len=-1 means str is NUL-terminated. */
 291 hb_buffer_serialize_format_t
 292 hb_buffer_serialize_format_from_string (const char *str, int len);
 293
 294 const char *
 295 hb_buffer_serialize_format_to_string (hb_buffer_serialize_format_t format);
 296
 297 const char **
 298 hb_buffer_serialize_list_formats (void);
 299
 300 /* Returns number of items, starting at start, that were serialized. */
 301 unsigned int
 302 hb_buffer_serialize_glyphs (hb_buffer_t *buffer,
 303                             unsigned int start,
 304                             unsigned int end,
 305                             char *buf,
 306                             unsigned int buf_size,
 307                             unsigned int *buf_consumed,
 308                             hb_font_t *font, /* May be NULL */
 309                             hb_buffer_serialize_format_t format,
 310                             hb_buffer_serialize_flags_t flags);
 311
 312 hb_bool_t
 313 hb_buffer_deserialize_glyphs (hb_buffer_t *buffer,
 314                               const char *buf,
 315                               unsigned int buf_len,
 316                               unsigned int *buf_consumed,
 317                               hb_font_t *font, /* May be NULL */
 318                               hb_buffer_serialize_format_t format);
 319
 320
 321 HB_END_DECLS
 322
 323 #endif /* HB_BUFFER_H */