hb-common.cc revision 675956aca01fc4e005a338af43d1c1f4f938abd1 
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
39hb_options_union_t _hb_options;
40
41void
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):
61 * @len:
62 *
63 *
64 *
65 * Return value:
66 *
67 * Since: 1.0
68 **/
69hb_tag_t
70hb_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: 1.0
96 **/
97void
98hb_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
109const 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):
119 * @len:
120 *
121 *
122 *
123 * Return value:
124 *
125 * Since: 1.0
126 **/
127hb_direction_t
128hb_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 **/
154const char *
155hb_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
167struct hb_language_impl_t {
168  const char s[1];
169};
170
171static 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
182static hb_bool_t
183lang_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
196static unsigned int
197lang_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
212struct 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
235static hb_language_item_t *langs;
236
237#ifdef HB_USE_ATEXIT
238static
239void 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
250static hb_language_item_t *
251lang_find_or_insert (const char *key)
252{
253retry:
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):
285 * @len:
286 *
287 *
288 *
289 * Return value:
290 *
291 * Since: 1.0
292 **/
293hb_language_t
294hb_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 **/
325const char *
326hb_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:
338 *
339 * Since: 1.0
340 **/
341hb_language_t
342hb_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 **/
368hb_script_t
369hb_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):
405 * @len:
406 *
407 *
408 *
409 * Return value:
410 *
411 * Since: 1.0
412 **/
413hb_script_t
414hb_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 **/
429hb_tag_t
430hb_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 **/
445hb_direction_t
446hb_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      return HB_DIRECTION_RTL;
497  }
498
499  return HB_DIRECTION_LTR;
500}
501
502
503/* hb_user_data_array_t */
504
505bool
506hb_user_data_array_t::set (hb_user_data_key_t *key,
507			   void *              data,
508			   hb_destroy_func_t   destroy,
509			   hb_bool_t           replace)
510{
511  if (!key)
512    return false;
513
514  if (replace) {
515    if (!data && !destroy) {
516      items.remove (key, lock);
517      return true;
518    }
519  }
520  hb_user_data_item_t item = {key, data, destroy};
521  bool ret = !!items.replace_or_insert (item, lock, replace);
522
523  return ret;
524}
525
526void *
527hb_user_data_array_t::get (hb_user_data_key_t *key)
528{
529  hb_user_data_item_t item = {NULL };
530
531  return items.find (key, &item, lock) ? item.data : NULL;
532}
533
534
535/* hb_version */
536
537/**
538 * hb_version:
539 * @major: (out): Library major version component.
540 * @minor: (out): Library minor version component.
541 * @micro: (out): Library micro version component.
542 *
543 * Returns library version as three integer components.
544 *
545 * Since: 1.0
546 **/
547void
548hb_version (unsigned int *major,
549	    unsigned int *minor,
550	    unsigned int *micro)
551{
552  *major = HB_VERSION_MAJOR;
553  *minor = HB_VERSION_MINOR;
554  *micro = HB_VERSION_MICRO;
555}
556
557/**
558 * hb_version_string:
559 *
560 * Returns library version as a string with three components.
561 *
562 * Return value: library version string.
563 *
564 * Since: 1.0
565 **/
566const char *
567hb_version_string (void)
568{
569  return HB_VERSION_STRING;
570}
571
572/**
573 * hb_version_atleast:
574 * @major:
575 * @minor:
576 * @micro:
577 *
578 *
579 *
580 * Return value:
581 *
582 * Since: 1.0
583 **/
584hb_bool_t
585hb_version_atleast (unsigned int major,
586		    unsigned int minor,
587		    unsigned int micro)
588{
589  return HB_VERSION_ATLEAST (major, minor, micro);
590}
591