1/*
2 * Copyright © 2009 Red Hat, Inc.
3 * Copyright © 2011 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, Roozbeh Pournader
27 */
28
29#include "hb.hh"
30
31#ifndef HB_NO_OT_TAG
32
33
34/* hb_script_t */
35
36static hb_tag_t
37hb_ot_old_tag_from_script (hb_script_t script)
38{
39 /* This seems to be accurate as of end of 2012. */
40
41 switch ((hb_tag_t) script)
42 {
43 case HB_SCRIPT_INVALID: return HB_OT_TAG_DEFAULT_SCRIPT;
44
45 /* KATAKANA and HIRAGANA both map to 'kana' */
46 case HB_SCRIPT_HIRAGANA: return HB_TAG('k','a','n','a');
47
48 /* Spaces at the end are preserved, unlike ISO 15924 */
49 case HB_SCRIPT_LAO: return HB_TAG('l','a','o',' ');
50 case HB_SCRIPT_YI: return HB_TAG('y','i',' ',' ');
51 /* Unicode-5.0 additions */
52 case HB_SCRIPT_NKO: return HB_TAG('n','k','o',' ');
53 /* Unicode-5.1 additions */
54 case HB_SCRIPT_VAI: return HB_TAG('v','a','i',' ');
55 }
56
57 /* Else, just change first char to lowercase and return */
58 return ((hb_tag_t) script) | 0x20000000u;
59}
60
61static hb_script_t
62hb_ot_old_tag_to_script (hb_tag_t tag)
63{
64 if (unlikely (tag == HB_OT_TAG_DEFAULT_SCRIPT))
65 return HB_SCRIPT_INVALID;
66
67 /* This side of the conversion is fully algorithmic. */
68
69 /* Any spaces at the end of the tag are replaced by repeating the last
70 * letter. Eg 'nko ' -> 'Nkoo' */
71 if (unlikely ((tag & 0x0000FF00u) == 0x00002000u))
72 tag |= (tag >> 8) & 0x0000FF00u; /* Copy second letter to third */
73 if (unlikely ((tag & 0x000000FFu) == 0x00000020u))
74 tag |= (tag >> 8) & 0x000000FFu; /* Copy third letter to fourth */
75
76 /* Change first char to uppercase and return */
77 return (hb_script_t) (tag & ~0x20000000u);
78}
79
80static hb_tag_t
81hb_ot_new_tag_from_script (hb_script_t script)
82{
83 switch ((hb_tag_t) script) {
84 case HB_SCRIPT_BENGALI: return HB_TAG('b','n','g','2');
85 case HB_SCRIPT_DEVANAGARI: return HB_TAG('d','e','v','2');
86 case HB_SCRIPT_GUJARATI: return HB_TAG('g','j','r','2');
87 case HB_SCRIPT_GURMUKHI: return HB_TAG('g','u','r','2');
88 case HB_SCRIPT_KANNADA: return HB_TAG('k','n','d','2');
89 case HB_SCRIPT_MALAYALAM: return HB_TAG('m','l','m','2');
90 case HB_SCRIPT_ORIYA: return HB_TAG('o','r','y','2');
91 case HB_SCRIPT_TAMIL: return HB_TAG('t','m','l','2');
92 case HB_SCRIPT_TELUGU: return HB_TAG('t','e','l','2');
93 case HB_SCRIPT_MYANMAR: return HB_TAG('m','y','m','2');
94 }
95
96 return HB_OT_TAG_DEFAULT_SCRIPT;
97}
98
99static hb_script_t
100hb_ot_new_tag_to_script (hb_tag_t tag)
101{
102 switch (tag) {
103 case HB_TAG('b','n','g','2'): return HB_SCRIPT_BENGALI;
104 case HB_TAG('d','e','v','2'): return HB_SCRIPT_DEVANAGARI;
105 case HB_TAG('g','j','r','2'): return HB_SCRIPT_GUJARATI;
106 case HB_TAG('g','u','r','2'): return HB_SCRIPT_GURMUKHI;
107 case HB_TAG('k','n','d','2'): return HB_SCRIPT_KANNADA;
108 case HB_TAG('m','l','m','2'): return HB_SCRIPT_MALAYALAM;
109 case HB_TAG('o','r','y','2'): return HB_SCRIPT_ORIYA;
110 case HB_TAG('t','m','l','2'): return HB_SCRIPT_TAMIL;
111 case HB_TAG('t','e','l','2'): return HB_SCRIPT_TELUGU;
112 case HB_TAG('m','y','m','2'): return HB_SCRIPT_MYANMAR;
113 }
114
115 return HB_SCRIPT_UNKNOWN;
116}
117
118#ifndef HB_DISABLE_DEPRECATED
119void
120hb_ot_tags_from_script (hb_script_t script,
121 hb_tag_t *script_tag_1,
122 hb_tag_t *script_tag_2)
123{
124 unsigned int count = 2;
125 hb_tag_t tags[2];
126 hb_ot_tags_from_script_and_language (script, HB_LANGUAGE_INVALID, &count, tags, nullptr, nullptr);
127 *script_tag_1 = count > 0 ? tags[0] : HB_OT_TAG_DEFAULT_SCRIPT;
128 *script_tag_2 = count > 1 ? tags[1] : HB_OT_TAG_DEFAULT_SCRIPT;
129}
130#endif
131
132/*
133 * Complete list at:
134 * https://docs.microsoft.com/en-us/typography/opentype/spec/scripttags
135 *
136 * Most of the script tags are the same as the ISO 15924 tag but lowercased.
137 * So we just do that, and handle the exceptional cases in a switch.
138 */
139
140static void
141hb_ot_all_tags_from_script (hb_script_t script,
142 unsigned int *count /* IN/OUT */,
143 hb_tag_t *tags /* OUT */)
144{
145 unsigned int i = 0;
146
147 hb_tag_t new_tag = hb_ot_new_tag_from_script (script);
148 if (unlikely (new_tag != HB_OT_TAG_DEFAULT_SCRIPT))
149 {
150 /* HB_SCRIPT_MYANMAR maps to 'mym2', but there is no 'mym3'. */
151 if (new_tag != HB_TAG('m','y','m','2'))
152 tags[i++] = new_tag | '3';
153 if (*count > i)
154 tags[i++] = new_tag;
155 }
156
157 if (*count > i)
158 {
159 hb_tag_t old_tag = hb_ot_old_tag_from_script (script);
160 if (old_tag != HB_OT_TAG_DEFAULT_SCRIPT)
161 tags[i++] = old_tag;
162 }
163
164 *count = i;
165}
166
167hb_script_t
168hb_ot_tag_to_script (hb_tag_t tag)
169{
170 unsigned char digit = tag & 0x000000FFu;
171 if (unlikely (digit == '2' || digit == '3'))
172 return hb_ot_new_tag_to_script (tag & 0xFFFFFF32);
173
174 return hb_ot_old_tag_to_script (tag);
175}
176
177
178/* hb_language_t */
179
180static bool
181subtag_matches (const char *lang_str,
182 const char *limit,
183 const char *subtag)
184{
185 do {
186 const char *s = strstr (lang_str, subtag);
187 if (!s || s >= limit)
188 return false;
189 if (!ISALNUM (s[strlen (subtag)]))
190 return true;
191 lang_str = s + strlen (subtag);
192 } while (true);
193}
194
195static hb_bool_t
196lang_matches (const char *lang_str, const char *spec)
197{
198 unsigned int len = strlen (spec);
199
200 return strncmp (lang_str, spec, len) == 0 &&
201 (lang_str[len] == '\0' || lang_str[len] == '-');
202}
203
204struct LangTag
205{
206 char language[4];
207 hb_tag_t tag;
208
209 int cmp (const char *a) const
210 {
211 const char *b = this->language;
212 unsigned int da, db;
213 const char *p;
214
215 p = strchr (a, '-');
216 da = p ? (unsigned int) (p - a) : strlen (a);
217
218 p = strchr (b, '-');
219 db = p ? (unsigned int) (p - b) : strlen (b);
220
221 return strncmp (a, b, hb_max (da, db));
222 }
223 int cmp (const LangTag *that) const
224 { return cmp (that->language); }
225};
226
227#include "hb-ot-tag-table.hh"
228
229/* The corresponding languages IDs for the following IDs are unclear,
230 * overlap, or are architecturally weird. Needs more research. */
231
232/*{"??", {HB_TAG('B','C','R',' ')}},*/ /* Bible Cree */
233/*{"zh?", {HB_TAG('C','H','N',' ')}},*/ /* Chinese (seen in Microsoft fonts) */
234/*{"ar-Syrc?", {HB_TAG('G','A','R',' ')}},*/ /* Garshuni */
235/*{"??", {HB_TAG('N','G','R',' ')}},*/ /* Nagari */
236/*{"??", {HB_TAG('Y','I','C',' ')}},*/ /* Yi Classic */
237/*{"zh?", {HB_TAG('Z','H','P',' ')}},*/ /* Chinese Phonetic */
238
239#ifndef HB_DISABLE_DEPRECATED
240hb_tag_t
241hb_ot_tag_from_language (hb_language_t language)
242{
243 unsigned int count = 1;
244 hb_tag_t tags[1];
245 hb_ot_tags_from_script_and_language (HB_SCRIPT_UNKNOWN, language, nullptr, nullptr, &count, tags);
246 return count > 0 ? tags[0] : HB_OT_TAG_DEFAULT_LANGUAGE;
247}
248#endif
249
250static void
251hb_ot_tags_from_language (const char *lang_str,
252 const char *limit,
253 unsigned int *count,
254 hb_tag_t *tags)
255{
256 const char *s;
257 unsigned int tag_idx;
258
259 /* Check for matches of multiple subtags. */
260 if (hb_ot_tags_from_complex_language (lang_str, limit, count, tags))
261 return;
262
263 /* Find a language matching in the first component. */
264 s = strchr (lang_str, '-');
265 {
266 if (s && limit - lang_str >= 6)
267 {
268 const char *extlang_end = strchr (s + 1, '-');
269 /* If there is an extended language tag, use it. */
270 if (3 == (extlang_end ? extlang_end - s - 1 : strlen (s + 1)) &&
271 ISALPHA (s[1]))
272 lang_str = s + 1;
273 }
274 if (hb_sorted_array (ot_languages).bfind (lang_str, &tag_idx))
275 {
276 unsigned int i;
277 while (tag_idx != 0 &&
278 0 == strcmp (ot_languages[tag_idx].language, ot_languages[tag_idx - 1].language))
279 tag_idx--;
280 for (i = 0;
281 i < *count &&
282 tag_idx + i < ARRAY_LENGTH (ot_languages) &&
283 0 == strcmp (ot_languages[tag_idx + i].language, ot_languages[tag_idx].language);
284 i++)
285 tags[i] = ot_languages[tag_idx + i].tag;
286 *count = i;
287 return;
288 }
289 }
290
291 if (!s)
292 s = lang_str + strlen (lang_str);
293 if (s - lang_str == 3) {
294 /* Assume it's ISO-639-3 and upper-case and use it. */
295 tags[0] = hb_tag_from_string (lang_str, s - lang_str) & ~0x20202000u;
296 *count = 1;
297 return;
298 }
299
300 *count = 0;
301}
302
303static bool
304parse_private_use_subtag (const char *private_use_subtag,
305 unsigned int *count,
306 hb_tag_t *tags,
307 const char *prefix,
308 unsigned char (*normalize) (unsigned char))
309{
310#ifdef HB_NO_LANGUAGE_PRIVATE_SUBTAG
311 return false;
312#endif
313
314 if (!(private_use_subtag && count && tags && *count)) return false;
315
316 const char *s = strstr (private_use_subtag, prefix);
317 if (!s) return false;
318
319 char tag[4];
320 int i;
321 s += strlen (prefix);
322 for (i = 0; i < 4 && ISALNUM (s[i]); i++)
323 tag[i] = normalize (s[i]);
324 if (!i) return false;
325
326 for (; i < 4; i++)
327 tag[i] = ' ';
328 tags[0] = HB_TAG (tag[0], tag[1], tag[2], tag[3]);
329 if ((tags[0] & 0xDFDFDFDF) == HB_OT_TAG_DEFAULT_SCRIPT)
330 tags[0] ^= ~0xDFDFDFDF;
331 *count = 1;
332 return true;
333}
334
335/**
336 * hb_ot_tags_from_script_and_language:
337 * @script: an #hb_script_t to convert.
338 * @language: an #hb_language_t to convert.
339 * @script_count: (allow-none): maximum number of script tags to retrieve (IN)
340 * and actual number of script tags retrieved (OUT)
341 * @script_tags: (out) (allow-none): array of size at least @script_count to store the
342 * script tag results
343 * @language_count: (allow-none): maximum number of language tags to retrieve
344 * (IN) and actual number of language tags retrieved (OUT)
345 * @language_tags: (out) (allow-none): array of size at least @language_count to store
346 * the language tag results
347 *
348 * Converts an #hb_script_t and an #hb_language_t to script and language tags.
349 *
350 * Since: 2.0.0
351 **/
352void
353hb_ot_tags_from_script_and_language (hb_script_t script,
354 hb_language_t language,
355 unsigned int *script_count /* IN/OUT */,
356 hb_tag_t *script_tags /* OUT */,
357 unsigned int *language_count /* IN/OUT */,
358 hb_tag_t *language_tags /* OUT */)
359{
360 bool needs_script = true;
361
362 if (language == HB_LANGUAGE_INVALID)
363 {
364 if (language_count && language_tags && *language_count)
365 *language_count = 0;
366 }
367 else
368 {
369 const char *lang_str, *s, *limit, *private_use_subtag;
370 bool needs_language;
371
372 lang_str = hb_language_to_string (language);
373 limit = nullptr;
374 private_use_subtag = nullptr;
375 if (lang_str[0] == 'x' && lang_str[1] == '-')
376 {
377 private_use_subtag = lang_str;
378 } else {
379 for (s = lang_str + 1; *s; s++)
380 {
381 if (s[-1] == '-' && s[1] == '-')
382 {
383 if (s[0] == 'x')
384 {
385 private_use_subtag = s;
386 if (!limit)
387 limit = s - 1;
388 break;
389 } else if (!limit)
390 {
391 limit = s - 1;
392 }
393 }
394 }
395 if (!limit)
396 limit = s;
397 }
398
399 needs_script = !parse_private_use_subtag (private_use_subtag, script_count, script_tags, "-hbsc", TOLOWER);
400 needs_language = !parse_private_use_subtag (private_use_subtag, language_count, language_tags, "-hbot", TOUPPER);
401
402 if (needs_language && language_count && language_tags && *language_count)
403 hb_ot_tags_from_language (lang_str, limit, language_count, language_tags);
404 }
405
406 if (needs_script && script_count && script_tags && *script_count)
407 hb_ot_all_tags_from_script (script, script_count, script_tags);
408}
409
410/**
411 * hb_ot_tag_to_language:
412 *
413 *
414 *
415 * Return value: (transfer none):
416 *
417 * Since: 0.9.2
418 **/
419hb_language_t
420hb_ot_tag_to_language (hb_tag_t tag)
421{
422 unsigned int i;
423
424 if (tag == HB_OT_TAG_DEFAULT_LANGUAGE)
425 return nullptr;
426
427 {
428 hb_language_t disambiguated_tag = hb_ot_ambiguous_tag_to_language (tag);
429 if (disambiguated_tag != HB_LANGUAGE_INVALID)
430 return disambiguated_tag;
431 }
432
433 for (i = 0; i < ARRAY_LENGTH (ot_languages); i++)
434 if (ot_languages[i].tag == tag)
435 return hb_language_from_string (ot_languages[i].language, -1);
436
437 /* If it's three letters long, assume it's ISO 639-3 and lower-case and use it
438 * (if it's not a registered tag, calling hb_ot_tag_from_language on the
439 * result might not return the same tag as the original tag).
440 * Else return a custom language in the form of "x-hbotABCD". */
441 {
442 char buf[11] = "x-hbot";
443 char *str = buf;
444 buf[6] = tag >> 24;
445 buf[7] = (tag >> 16) & 0xFF;
446 buf[8] = (tag >> 8) & 0xFF;
447 buf[9] = tag & 0xFF;
448 if (buf[9] == 0x20)
449 {
450 buf[9] = '\0';
451 if (ISALPHA (buf[6]) && ISALPHA (buf[7]) && ISALPHA (buf[8]))
452 {
453 buf[6] = TOLOWER (buf[6]);
454 buf[7] = TOLOWER (buf[7]);
455 buf[8] = TOLOWER (buf[8]);
456 str += 6;
457 }
458 }
459 buf[10] = '\0';
460 return hb_language_from_string (str, -1);
461 }
462}
463
464/**
465 * hb_ot_tags_to_script_and_language:
466 * @script_tag: a script tag
467 * @language_tag: a language tag
468 * @script: (allow-none): the #hb_script_t corresponding to @script_tag (OUT).
469 * @language: (allow-none): the #hb_language_t corresponding to @script_tag and
470 * @language_tag (OUT).
471 *
472 * Converts a script tag and a language tag to an #hb_script_t and an
473 * #hb_language_t.
474 *
475 * Since: 2.0.0
476 **/
477void
478hb_ot_tags_to_script_and_language (hb_tag_t script_tag,
479 hb_tag_t language_tag,
480 hb_script_t *script /* OUT */,
481 hb_language_t *language /* OUT */)
482{
483 hb_script_t script_out = hb_ot_tag_to_script (script_tag);
484 if (script)
485 *script = script_out;
486 if (language)
487 {
488 unsigned int script_count = 1;
489 hb_tag_t primary_script_tag[1];
490 hb_ot_tags_from_script_and_language (script_out,
491 HB_LANGUAGE_INVALID,
492 &script_count,
493 primary_script_tag,
494 nullptr, nullptr);
495 *language = hb_ot_tag_to_language (language_tag);
496 if (script_count == 0 || primary_script_tag[0] != script_tag)
497 {
498 unsigned char *buf;
499 const char *lang_str = hb_language_to_string (*language);
500 size_t len = strlen (lang_str);
501 buf = (unsigned char *) malloc (len + 11);
502 if (unlikely (!buf))
503 {
504 *language = nullptr;
505 }
506 else
507 {
508 memcpy (buf, lang_str, len);
509 if (lang_str[0] != 'x' || lang_str[1] != '-') {
510 buf[len++] = '-';
511 buf[len++] = 'x';
512 }
513 buf[len++] = '-';
514 buf[len++] = 'h';
515 buf[len++] = 'b';
516 buf[len++] = 's';
517 buf[len++] = 'c';
518 buf[len++] = script_tag >> 24;
519 buf[len++] = (script_tag >> 16) & 0xFF;
520 buf[len++] = (script_tag >> 8) & 0xFF;
521 buf[len++] = script_tag & 0xFF;
522 *language = hb_language_from_string ((char *) buf, len);
523 free (buf);
524 }
525 }
526 }
527}
528
529#ifdef MAIN
530static inline void
531test_langs_sorted ()
532{
533 for (unsigned int i = 1; i < ARRAY_LENGTH (ot_languages); i++)
534 {
535 int c = ot_languages[i].cmp (&ot_languages[i - 1]);
536 if (c > 0)
537 {
538 fprintf (stderr, "ot_languages not sorted at index %d: %s %d %s\n",
539 i, ot_languages[i-1].language, c, ot_languages[i].language);
540 abort();
541 }
542 }
543}
544
545int
546main ()
547{
548 test_langs_sorted ();
549 return 0;
550}
551
552#endif
553
554
555#endif
556