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 { /*< flags >*/
 175   HB_BUFFER_FLAG_DEFAULT                        = 0x00000000u,
 176   HB_BUFFER_FLAG_BOT                            = 0x00000001u, /* Beginning-of-text */
 177   HB_BUFFER_FLAG_EOT                            = 0x00000002u, /* End-of-text */
 178   HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES    = 0x00000004u
 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
 190 #define HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT 0xFFFDu
 191
 192 /* Sets codepoint used to replace invalid UTF-8/16/32 entries.
 193  * Default is 0xFFFDu. */
 194 void
 195 hb_buffer_set_replacement_codepoint (hb_buffer_t    *buffer,
 196                                      hb_codepoint_t  replacement);
 197
 198 hb_codepoint_t
 199 hb_buffer_get_replacement_codepoint (hb_buffer_t    *buffer);
 200
 201
 202 /* Resets the buffer.  Afterwards it's as if it was just created,
 203  * except that it has a larger buffer allocated perhaps... */
 204 void
 205 hb_buffer_reset (hb_buffer_t *buffer);
 206
 207 /* Like reset, but does NOT clear unicode_funcs and replacement_codepoint. */
 208 void
 209 hb_buffer_clear_contents (hb_buffer_t *buffer);
 210
 211 /* Returns false if allocation failed */
 212 hb_bool_t
 213 hb_buffer_pre_allocate (hb_buffer_t  *buffer,
 214                         unsigned int  size);
 215
 216
 217 /* Returns false if allocation has failed before */
 218 hb_bool_t
 219 hb_buffer_allocation_successful (hb_buffer_t  *buffer);
 220
 221 void
 222 hb_buffer_reverse (hb_buffer_t *buffer);
 223
 224 void
 225 hb_buffer_reverse_clusters (hb_buffer_t *buffer);
 226
 227
 228 /* Filling the buffer in */
 229
 230 void
 231 hb_buffer_add (hb_buffer_t    *buffer,
 232                hb_codepoint_t  codepoint,
 233                unsigned int    cluster);
 234
 235 void
 236 hb_buffer_add_utf8 (hb_buffer_t  *buffer,
 237                     const char   *text,
 238                     int           text_length,
 239                     unsigned int  item_offset,
 240                     int           item_length);
 241
 242 void
 243 hb_buffer_add_utf16 (hb_buffer_t    *buffer,
 244                      const uint16_t *text,
 245                      int             text_length,
 246                      unsigned int    item_offset,
 247                      int             item_length);
 248
 249 void
 250 hb_buffer_add_utf32 (hb_buffer_t    *buffer,
 251                      const uint32_t *text,
 252                      int             text_length,
 253                      unsigned int    item_offset,
 254                      int             item_length);
 255
 256 /* Like add_utf32 but does NOT check for invalid Unicode codepoints. */
 257 void
 258 hb_buffer_add_codepoints (hb_buffer_t          *buffer,
 259                           const hb_codepoint_t *text,
 260                           int                   text_length,
 261                           unsigned int          item_offset,
 262                           int                   item_length);
 263
 264
 265 /* Clears any new items added at the end */
 266 hb_bool_t
 267 hb_buffer_set_length (hb_buffer_t  *buffer,
 268                       unsigned int  length);
 269
 270 /* Return value valid as long as buffer not modified */
 271 unsigned int
 272 hb_buffer_get_length (hb_buffer_t *buffer);
 273
 274 /* Getting glyphs out of the buffer */
 275
 276 /* Return value valid as long as buffer not modified */
 277 hb_glyph_info_t *
 278 hb_buffer_get_glyph_infos (hb_buffer_t  *buffer,
 279                            unsigned int *length);
 280
 281 /* Return value valid as long as buffer not modified */
 282 hb_glyph_position_t *
 283 hb_buffer_get_glyph_positions (hb_buffer_t  *buffer,
 284                                unsigned int *length);
 285
 286
 287 /* Reorders a glyph buffer to have canonical in-cluster glyph order / position.
 288  * The resulting clusters should behave identical to pre-reordering clusters.
 289  * NOTE: This has nothing to do with Unicode normalization. */
 290 void
 291 hb_buffer_normalize_glyphs (hb_buffer_t *buffer);
 292
 293
 294 /*
 295  * Serialize
 296  */
 297
 298 typedef enum { /*< flags >*/
 299   HB_BUFFER_SERIALIZE_FLAG_DEFAULT              = 0x00000000u,
 300   HB_BUFFER_SERIALIZE_FLAG_NO_CLUSTERS          = 0x00000001u,
 301   HB_BUFFER_SERIALIZE_FLAG_NO_POSITIONS         = 0x00000002u,
 302   HB_BUFFER_SERIALIZE_FLAG_NO_GLYPH_NAMES       = 0x00000004u
 303 } hb_buffer_serialize_flags_t;
 304
 305 typedef enum {
 306   HB_BUFFER_SERIALIZE_FORMAT_TEXT       = HB_TAG('T','E','X','T'),
 307   HB_BUFFER_SERIALIZE_FORMAT_JSON       = HB_TAG('J','S','O','N'),
 308   HB_BUFFER_SERIALIZE_FORMAT_INVALID    = HB_TAG_NONE
 309 } hb_buffer_serialize_format_t;
 310
 311 /* len=-1 means str is NUL-terminated. */
 312 hb_buffer_serialize_format_t
 313 hb_buffer_serialize_format_from_string (const char *str, int len);
 314
 315 const char *
 316 hb_buffer_serialize_format_to_string (hb_buffer_serialize_format_t format);
 317
 318 const char **
 319 hb_buffer_serialize_list_formats (void);
 320
 321 /* Returns number of items, starting at start, that were serialized. */
 322 unsigned int
 323 hb_buffer_serialize_glyphs (hb_buffer_t *buffer,
 324                             unsigned int start,
 325                             unsigned int end,
 326                             char *buf,
 327                             unsigned int buf_size,
 328                             unsigned int *buf_consumed, /* May be NULL */
 329                             hb_font_t *font, /* May be NULL */
 330                             hb_buffer_serialize_format_t format,
 331                             hb_buffer_serialize_flags_t flags);
 332
 333 hb_bool_t
 334 hb_buffer_deserialize_glyphs (hb_buffer_t *buffer,
 335                               const char *buf,
 336                               int buf_len, /* -1 means nul-terminated */
 337                               const char **end_ptr, /* May be NULL */
 338                               hb_font_t *font, /* May be NULL */
 339                               hb_buffer_serialize_format_t format);
 340
 341
 342 HB_END_DECLS
 343
 344 #endif /* HB_BUFFER_H */