third_party/harfbuzz-ng/src/hb-common.cc

   1 /*
   2  * Copyright © 2009,2010  Red Hat, Inc.
   3  * Copyright © 2011,2012  Google, Inc.
   4  *
   5  *  This is part of HarfBuzz, a text shaping library.
   6  *
   7  * Permission is hereby granted, without written agreement and without
   8  * license or royalty fees, to use, copy, modify, and distribute this
   9  * software and its documentation for any purpose, provided that the
  10  * above copyright notice and the following two paragraphs appear in
  11  * all copies of this software.
  12  *
  13  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  14  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  15  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  16  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  17  * DAMAGE.
  18  *
  19  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  20  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  21  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  22  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  23  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  24  *
  25  * Red Hat Author(s): Behdad Esfahbod
  26  * Google Author(s): Behdad Esfahbod
  27  */
  28
  29 #include "hb-private.hh"
  30
  31 #include "hb-mutex-private.hh"
  32 #include "hb-object-private.hh"
  33
  34 #include <locale.h>
  35
  36
  37 /* hb_options_t */
  38
  39 hb_options_union_t _hb_options;
  40
  41 void
  42 _hb_options_init (void)
  43 {
  44   hb_options_union_t u;
  45   u.i = 0;
  46   u.opts.initialized = 1;
  47
  48   char *c = getenv ("HB_OPTIONS");
  49   u.opts.uniscribe_bug_compatible = c && strstr (c, "uniscribe-bug-compatible");
  50
  51   /* This is idempotent and threadsafe. */
  52   _hb_options = u;
  53 }
  54
  55
  56 /* hb_tag_t */
  57
  58 /**
  59  * hb_tag_from_string:
  60  * @str: (array length=len) (element-type uint8_t):
  61  * @len:
  62  *
  63  *
  64  *
  65  * Return value:
  66  *
  67  * Since: 1.0
  68  **/
  69 hb_tag_t
  70 hb_tag_from_string (const char *str, int len)
  71 {
  72   char tag[4];
  73   unsigned int i;
  74
  75   if (!str || !len || !*str)
  76     return HB_TAG_NONE;
  77
  78   if (len < 0 || len > 4)
  79     len = 4;
  80   for (i = 0; i < (unsigned) len && str[i]; i++)
  81     tag[i] = str[i];
  82   for (; i < 4; i++)
  83     tag[i] = ' ';
  84
  85   return HB_TAG_CHAR4 (tag);
  86 }
  87
  88 /**
  89  * hb_tag_to_string:
  90  * @tag:
  91  * @buf: (array fixed-size=4):
  92  *
  93  *
  94  *
  95  * Since: 0.9.5
  96  **/
  97 void
  98 hb_tag_to_string (hb_tag_t tag, char *buf)
  99 {
 100   buf[0] = (char) (uint8_t) (tag >> 24);
 101   buf[1] = (char) (uint8_t) (tag >> 16);
 102   buf[2] = (char) (uint8_t) (tag >>  8);
 103   buf[3] = (char) (uint8_t) (tag >>  0);
 104 }
 105
 106
 107 /* hb_direction_t */
 108
 109 const char direction_strings[][4] = {
 110   "ltr",
 111   "rtl",
 112   "ttb",
 113   "btt"
 114 };
 115
 116 /**
 117  * hb_direction_from_string:
 118  * @str: (array length=len) (element-type uint8_t):
 119  * @len:
 120  *
 121  *
 122  *
 123  * Return value:
 124  *
 125  * Since: 1.0
 126  **/
 127 hb_direction_t
 128 hb_direction_from_string (const char *str, int len)
 129 {
 130   if (unlikely (!str || !len || !*str))
 131     return HB_DIRECTION_INVALID;
 132
 133   /* Lets match loosely: just match the first letter, such that
 134    * all of "ltr", "left-to-right", etc work!
 135    */
 136   char c = TOLOWER (str[0]);
 137   for (unsigned int i = 0; i < ARRAY_LENGTH (direction_strings); i++)
 138     if (c == direction_strings[i][0])
 139       return (hb_direction_t) (HB_DIRECTION_LTR + i);
 140
 141   return HB_DIRECTION_INVALID;
 142 }
 143
 144 /**
 145  * hb_direction_to_string:
 146  * @direction:
 147  *
 148  *
 149  *
 150  * Return value: (transfer none):
 151  *
 152  * Since: 1.0
 153  **/
 154 const char *
 155 hb_direction_to_string (hb_direction_t direction)
 156 {
 157   if (likely ((unsigned int) (direction - HB_DIRECTION_LTR)
 158               < ARRAY_LENGTH (direction_strings)))
 159     return direction_strings[direction - HB_DIRECTION_LTR];
 160
 161   return "invalid";
 162 }
 163
 164
 165 /* hb_language_t */
 166
 167 struct hb_language_impl_t {
 168   const char s[1];
 169 };
 170
 171 static const char canon_map[256] = {
 172    0,   0,   0,   0,   0,   0,   0,   0,    0,   0,   0,   0,   0,   0,   0,   0,
 173    0,   0,   0,   0,   0,   0,   0,   0,    0,   0,   0,   0,   0,   0,   0,   0,
 174    0,   0,   0,   0,   0,   0,   0,   0,    0,   0,   0,   0,   0,  '-',  0,   0,
 175   '0', '1', '2', '3', '4', '5', '6', '7',  '8', '9',  0,   0,   0,   0,   0,   0,
 176   '-', 'a', 'b', 'c', 'd', 'e', 'f', 'g',  'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
 177   'p', 'q', 'r', 's', 't', 'u', 'v', 'w',  'x', 'y', 'z',  0,   0,   0,   0,  '-',
 178    0,  'a', 'b', 'c', 'd', 'e', 'f', 'g',  'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
 179   'p', 'q', 'r', 's', 't', 'u', 'v', 'w',  'x', 'y', 'z',  0,   0,   0,   0,   0
 180 };
 181
 182 static bool
 183 lang_equal (hb_language_t  v1,
 184             const void    *v2)
 185 {
 186   const unsigned char *p1 = (const unsigned char *) v1;
 187   const unsigned char *p2 = (const unsigned char *) v2;
 188
 189   while (*p1 && *p1 == canon_map[*p2])
 190     p1++, p2++;
 191
 192   return *p1 == canon_map[*p2];
 193 }
 194
 195 #if 0
 196 static unsigned int
 197 lang_hash (const void *key)
 198 {
 199   const unsigned char *p = key;
 200   unsigned int h = 0;
 201   while (canon_map[*p])
 202     {
 203       h = (h << 5) - h + canon_map[*p];
 204       p++;
 205     }
 206
 207   return h;
 208 }
 209 #endif
 210
 211
 212 struct hb_language_item_t {
 213
 214   struct hb_language_item_t *next;
 215   hb_language_t lang;
 216
 217   inline bool operator == (const char *s) const {
 218     return lang_equal (lang, s);
 219   }
 220
 221   inline hb_language_item_t & operator = (const char *s) {
 222     lang = (hb_language_t) strdup (s);
 223     for (unsigned char *p = (unsigned char *) lang; *p; p++)
 224       *p = canon_map[*p];
 225
 226     return *this;
 227   }
 228
 229   void finish (void) { free ((void *) lang); }
 230 };
 231
 232
 233 /* Thread-safe lock-free language list */
 234
 235 static hb_language_item_t *langs;
 236
 237 #ifdef HB_USE_ATEXIT
 238 static
 239 void free_langs (void)
 240 {
 241   while (langs) {
 242     hb_language_item_t *next = langs->next;
 243     langs->finish ();
 244     free (langs);
 245     langs = next;
 246   }
 247 }
 248 #endif
 249
 250 static hb_language_item_t *
 251 lang_find_or_insert (const char *key)
 252 {
 253 retry:
 254   hb_language_item_t *first_lang = (hb_language_item_t *) hb_atomic_ptr_get (&langs);
 255
 256   for (hb_language_item_t *lang = first_lang; lang; lang = lang->next)
 257     if (*lang == key)
 258       return lang;
 259
 260   /* Not found; allocate one. */
 261   hb_language_item_t *lang = (hb_language_item_t *) calloc (1, sizeof (hb_language_item_t));
 262   if (unlikely (!lang))
 263     return NULL;
 264   lang->next = first_lang;
 265   *lang = key;
 266
 267   if (!hb_atomic_ptr_cmpexch (&langs, first_lang, lang)) {
 268     lang->finish ();
 269     free (lang);
 270     goto retry;
 271   }
 272
 273 #ifdef HB_USE_ATEXIT
 274   if (!first_lang)
 275     atexit (free_langs); /* First person registers atexit() callback. */
 276 #endif
 277
 278   return lang;
 279 }
 280
 281
 282 /**
 283  * hb_language_from_string:
 284  * @str: (array length=len) (element-type uint8_t):
 285  * @len:
 286  *
 287  *
 288  *
 289  * Return value: (transfer none):
 290  *
 291  * Since: 1.0
 292  **/
 293 hb_language_t
 294 hb_language_from_string (const char *str, int len)
 295 {
 296   char strbuf[64];
 297
 298   if (!str || !len || !*str)
 299     return HB_LANGUAGE_INVALID;
 300
 301   if (len >= 0)
 302   {
 303     /* NUL-terminate it. */
 304     len = MIN (len, (int) sizeof (strbuf) - 1);
 305     memcpy (strbuf, str, len);
 306     strbuf[len] = '\0';
 307     str = strbuf;
 308   }
 309
 310   hb_language_item_t *item = lang_find_or_insert (str);
 311
 312   return likely (item) ? item->lang : HB_LANGUAGE_INVALID;
 313 }
 314
 315 /**
 316  * hb_language_to_string:
 317  * @language:
 318  *
 319  *
 320  *
 321  * Return value: (transfer none):
 322  *
 323  * Since: 1.0
 324  **/
 325 const char *
 326 hb_language_to_string (hb_language_t language)
 327 {
 328   /* This is actually NULL-safe! */
 329   return language->s;
 330 }
 331
 332 /**
 333  * hb_language_get_default:
 334  *
 335  *
 336  *
 337  * Return value: (transfer none):
 338  *
 339  * Since: 1.0
 340  **/
 341 hb_language_t
 342 hb_language_get_default (void)
 343 {
 344   static hb_language_t default_language = HB_LANGUAGE_INVALID;
 345
 346   hb_language_t language = (hb_language_t) hb_atomic_ptr_get (&default_language);
 347   if (unlikely (language == HB_LANGUAGE_INVALID)) {
 348     language = hb_language_from_string (setlocale (LC_CTYPE, NULL), -1);
 349     (void) hb_atomic_ptr_cmpexch (&default_language, HB_LANGUAGE_INVALID, language);
 350   }
 351
 352   return default_language;
 353 }
 354
 355
 356 /* hb_script_t */
 357
 358 /**
 359  * hb_script_from_iso15924_tag:
 360  * @tag:
 361  *
 362  *
 363  *
 364  * Return value:
 365  *
 366  * Since: 1.0
 367  **/
 368 hb_script_t
 369 hb_script_from_iso15924_tag (hb_tag_t tag)
 370 {
 371   if (unlikely (tag == HB_TAG_NONE))
 372     return HB_SCRIPT_INVALID;
 373
 374   /* Be lenient, adjust case (one capital letter followed by three small letters) */
 375   tag = (tag & 0xDFDFDFDFu) | 0x00202020u;
 376
 377   switch (tag) {
 378
 379     /* These graduated from the 'Q' private-area codes, but
 380      * the old code is still aliased by Unicode, and the Qaai
 381      * one in use by ICU. */
 382     case HB_TAG('Q','a','a','i'): return HB_SCRIPT_INHERITED;
 383     case HB_TAG('Q','a','a','c'): return HB_SCRIPT_COPTIC;
 384
 385     /* Script variants from http://unicode.org/iso15924/ */
 386     case HB_TAG('C','y','r','s'): return HB_SCRIPT_CYRILLIC;
 387     case HB_TAG('L','a','t','f'): return HB_SCRIPT_LATIN;
 388     case HB_TAG('L','a','t','g'): return HB_SCRIPT_LATIN;
 389     case HB_TAG('S','y','r','e'): return HB_SCRIPT_SYRIAC;
 390     case HB_TAG('S','y','r','j'): return HB_SCRIPT_SYRIAC;
 391     case HB_TAG('S','y','r','n'): return HB_SCRIPT_SYRIAC;
 392   }
 393
 394   /* If it looks right, just use the tag as a script */
 395   if (((uint32_t) tag & 0xE0E0E0E0u) == 0x40606060u)
 396     return (hb_script_t) tag;
 397
 398   /* Otherwise, return unknown */
 399   return HB_SCRIPT_UNKNOWN;
 400 }
 401
 402 /**
 403  * hb_script_from_string:
 404  * @s: (array length=len) (element-type uint8_t):
 405  * @len:
 406  *
 407  *
 408  *
 409  * Return value:
 410  *
 411  * Since: 1.0
 412  **/
 413 hb_script_t
 414 hb_script_from_string (const char *s, int len)
 415 {
 416   return hb_script_from_iso15924_tag (hb_tag_from_string (s, len));
 417 }
 418
 419 /**
 420  * hb_script_to_iso15924_tag:
 421  * @script:
 422  *
 423  *
 424  *
 425  * Return value:
 426  *
 427  * Since: 1.0
 428  **/
 429 hb_tag_t
 430 hb_script_to_iso15924_tag (hb_script_t script)
 431 {
 432   return (hb_tag_t) script;
 433 }
 434
 435 /**
 436  * hb_script_get_horizontal_direction:
 437  * @script:
 438  *
 439  *
 440  *
 441  * Return value:
 442  *
 443  * Since: 1.0
 444  **/
 445 hb_direction_t
 446 hb_script_get_horizontal_direction (hb_script_t script)
 447 {
 448   /* http://goo.gl/x9ilM */
 449   switch ((hb_tag_t) script)
 450   {
 451     /* Unicode-1.1 additions */
 452     case HB_SCRIPT_ARABIC:
 453     case HB_SCRIPT_HEBREW:
 454
 455     /* Unicode-3.0 additions */
 456     case HB_SCRIPT_SYRIAC:
 457     case HB_SCRIPT_THAANA:
 458
 459     /* Unicode-4.0 additions */
 460     case HB_SCRIPT_CYPRIOT:
 461
 462     /* Unicode-4.1 additions */
 463     case HB_SCRIPT_KHAROSHTHI:
 464
 465     /* Unicode-5.0 additions */
 466     case HB_SCRIPT_PHOENICIAN:
 467     case HB_SCRIPT_NKO:
 468
 469     /* Unicode-5.1 additions */
 470     case HB_SCRIPT_LYDIAN:
 471
 472     /* Unicode-5.2 additions */
 473     case HB_SCRIPT_AVESTAN:
 474     case HB_SCRIPT_IMPERIAL_ARAMAIC:
 475     case HB_SCRIPT_INSCRIPTIONAL_PAHLAVI:
 476     case HB_SCRIPT_INSCRIPTIONAL_PARTHIAN:
 477     case HB_SCRIPT_OLD_SOUTH_ARABIAN:
 478     case HB_SCRIPT_OLD_TURKIC:
 479     case HB_SCRIPT_SAMARITAN:
 480
 481     /* Unicode-6.0 additions */
 482     case HB_SCRIPT_MANDAIC:
 483
 484     /* Unicode-6.1 additions */
 485     case HB_SCRIPT_MEROITIC_CURSIVE:
 486     case HB_SCRIPT_MEROITIC_HIEROGLYPHS:
 487
 488     /* Unicode-7.0 additions */
 489     case HB_SCRIPT_MANICHAEAN:
 490     case HB_SCRIPT_MENDE_KIKAKUI:
 491     case HB_SCRIPT_NABATAEAN:
 492     case HB_SCRIPT_OLD_NORTH_ARABIAN:
 493     case HB_SCRIPT_PALMYRENE:
 494     case HB_SCRIPT_PSALTER_PAHLAVI:
 495
 496     /* Unicode-8.0 additions */
 497     case HB_SCRIPT_OLD_HUNGARIAN:
 498
 499       return HB_DIRECTION_RTL;
 500   }
 501
 502   return HB_DIRECTION_LTR;
 503 }
 504
 505
 506 /* hb_user_data_array_t */
 507
 508 bool
 509 hb_user_data_array_t::set (hb_user_data_key_t *key,
 510                            void *              data,
 511                            hb_destroy_func_t   destroy,
 512                            hb_bool_t           replace)
 513 {
 514   if (!key)
 515     return false;
 516
 517   if (replace) {
 518     if (!data && !destroy) {
 519       items.remove (key, lock);
 520       return true;
 521     }
 522   }
 523   hb_user_data_item_t item = {key, data, destroy};
 524   bool ret = !!items.replace_or_insert (item, lock, replace);
 525
 526   return ret;
 527 }
 528
 529 void *
 530 hb_user_data_array_t::get (hb_user_data_key_t *key)
 531 {
 532   hb_user_data_item_t item = {NULL };
 533
 534   return items.find (key, &item, lock) ? item.data : NULL;
 535 }
 536
 537
 538 /* hb_version */
 539
 540 /**
 541  * hb_version:
 542  * @major: (out): Library major version component.
 543  * @minor: (out): Library minor version component.
 544  * @micro: (out): Library micro version component.
 545  *
 546  * Returns library version as three integer components.
 547  *
 548  * Since: 1.0
 549  **/
 550 void
 551 hb_version (unsigned int *major,
 552             unsigned int *minor,
 553             unsigned int *micro)
 554 {
 555   *major = HB_VERSION_MAJOR;
 556   *minor = HB_VERSION_MINOR;
 557   *micro = HB_VERSION_MICRO;
 558 }
 559
 560 /**
 561  * hb_version_string:
 562  *
 563  * Returns library version as a string with three components.
 564  *
 565  * Return value: library version string.
 566  *
 567  * Since: 1.0
 568  **/
 569 const char *
 570 hb_version_string (void)
 571 {
 572   return HB_VERSION_STRING;
 573 }
 574
 575 /**
 576  * hb_version_atleast:
 577  * @major:
 578  * @minor:
 579  * @micro:
 580  *
 581  *
 582  *
 583  * Return value:
 584  *
 585  * Since: 0.9.30
 586  **/
 587 hb_bool_t
 588 hb_version_atleast (unsigned int major,
 589                     unsigned int minor,
 590                     unsigned int micro)
 591 {
 592   return HB_VERSION_ATLEAST (major, minor, micro);
 593 }