Fri, 16 Jan 2015 18:13:44 +0100
Integrate suggestion from review to improve consistency with existing code.
1 /*
2 * Copyright © 2007,2008,2009,2010 Red Hat, Inc.
3 * Copyright © 2010,2012,2013 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 */
29 #ifndef HB_OT_LAYOUT_GSUB_TABLE_HH
30 #define HB_OT_LAYOUT_GSUB_TABLE_HH
32 #include "hb-ot-layout-gsubgpos-private.hh"
35 namespace OT {
38 struct SingleSubstFormat1
39 {
40 inline void closure (hb_closure_context_t *c) const
41 {
42 TRACE_CLOSURE (this);
43 Coverage::Iter iter;
44 for (iter.init (this+coverage); iter.more (); iter.next ()) {
45 hb_codepoint_t glyph_id = iter.get_glyph ();
46 if (c->glyphs->has (glyph_id))
47 c->glyphs->add ((glyph_id + deltaGlyphID) & 0xFFFF);
48 }
49 }
51 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
52 {
53 TRACE_COLLECT_GLYPHS (this);
54 Coverage::Iter iter;
55 for (iter.init (this+coverage); iter.more (); iter.next ()) {
56 hb_codepoint_t glyph_id = iter.get_glyph ();
57 c->input->add (glyph_id);
58 c->output->add ((glyph_id + deltaGlyphID) & 0xFFFF);
59 }
60 }
62 inline const Coverage &get_coverage (void) const
63 {
64 return this+coverage;
65 }
67 inline bool would_apply (hb_would_apply_context_t *c) const
68 {
69 TRACE_WOULD_APPLY (this);
70 return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
71 }
73 inline bool apply (hb_apply_context_t *c) const
74 {
75 TRACE_APPLY (this);
76 hb_codepoint_t glyph_id = c->buffer->cur().codepoint;
77 unsigned int index = (this+coverage).get_coverage (glyph_id);
78 if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
80 /* According to the Adobe Annotated OpenType Suite, result is always
81 * limited to 16bit. */
82 glyph_id = (glyph_id + deltaGlyphID) & 0xFFFF;
83 c->replace_glyph (glyph_id);
85 return TRACE_RETURN (true);
86 }
88 inline bool serialize (hb_serialize_context_t *c,
89 Supplier<GlyphID> &glyphs,
90 unsigned int num_glyphs,
91 int delta)
92 {
93 TRACE_SERIALIZE (this);
94 if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
95 if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return TRACE_RETURN (false);
96 deltaGlyphID.set (delta); /* TODO(serilaize) overflow? */
97 return TRACE_RETURN (true);
98 }
100 inline bool sanitize (hb_sanitize_context_t *c) {
101 TRACE_SANITIZE (this);
102 return TRACE_RETURN (coverage.sanitize (c, this) && deltaGlyphID.sanitize (c));
103 }
105 protected:
106 USHORT format; /* Format identifier--format = 1 */
107 OffsetTo<Coverage>
108 coverage; /* Offset to Coverage table--from
109 * beginning of Substitution table */
110 SHORT deltaGlyphID; /* Add to original GlyphID to get
111 * substitute GlyphID */
112 public:
113 DEFINE_SIZE_STATIC (6);
114 };
116 struct SingleSubstFormat2
117 {
118 inline void closure (hb_closure_context_t *c) const
119 {
120 TRACE_CLOSURE (this);
121 Coverage::Iter iter;
122 for (iter.init (this+coverage); iter.more (); iter.next ()) {
123 if (c->glyphs->has (iter.get_glyph ()))
124 c->glyphs->add (substitute[iter.get_coverage ()]);
125 }
126 }
128 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
129 {
130 TRACE_COLLECT_GLYPHS (this);
131 Coverage::Iter iter;
132 for (iter.init (this+coverage); iter.more (); iter.next ()) {
133 c->input->add (iter.get_glyph ());
134 c->output->add (substitute[iter.get_coverage ()]);
135 }
136 }
138 inline const Coverage &get_coverage (void) const
139 {
140 return this+coverage;
141 }
143 inline bool would_apply (hb_would_apply_context_t *c) const
144 {
145 TRACE_WOULD_APPLY (this);
146 return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
147 }
149 inline bool apply (hb_apply_context_t *c) const
150 {
151 TRACE_APPLY (this);
152 hb_codepoint_t glyph_id = c->buffer->cur().codepoint;
153 unsigned int index = (this+coverage).get_coverage (glyph_id);
154 if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
156 if (unlikely (index >= substitute.len)) return TRACE_RETURN (false);
158 glyph_id = substitute[index];
159 c->replace_glyph (glyph_id);
161 return TRACE_RETURN (true);
162 }
164 inline bool serialize (hb_serialize_context_t *c,
165 Supplier<GlyphID> &glyphs,
166 Supplier<GlyphID> &substitutes,
167 unsigned int num_glyphs)
168 {
169 TRACE_SERIALIZE (this);
170 if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
171 if (unlikely (!substitute.serialize (c, substitutes, num_glyphs))) return TRACE_RETURN (false);
172 if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return TRACE_RETURN (false);
173 return TRACE_RETURN (true);
174 }
176 inline bool sanitize (hb_sanitize_context_t *c) {
177 TRACE_SANITIZE (this);
178 return TRACE_RETURN (coverage.sanitize (c, this) && substitute.sanitize (c));
179 }
181 protected:
182 USHORT format; /* Format identifier--format = 2 */
183 OffsetTo<Coverage>
184 coverage; /* Offset to Coverage table--from
185 * beginning of Substitution table */
186 ArrayOf<GlyphID>
187 substitute; /* Array of substitute
188 * GlyphIDs--ordered by Coverage Index */
189 public:
190 DEFINE_SIZE_ARRAY (6, substitute);
191 };
193 struct SingleSubst
194 {
195 inline bool serialize (hb_serialize_context_t *c,
196 Supplier<GlyphID> &glyphs,
197 Supplier<GlyphID> &substitutes,
198 unsigned int num_glyphs)
199 {
200 TRACE_SERIALIZE (this);
201 if (unlikely (!c->extend_min (u.format))) return TRACE_RETURN (false);
202 unsigned int format = 2;
203 int delta;
204 if (num_glyphs) {
205 format = 1;
206 /* TODO(serialize) check for wrap-around */
207 delta = substitutes[0] - glyphs[0];
208 for (unsigned int i = 1; i < num_glyphs; i++)
209 if (delta != substitutes[i] - glyphs[i]) {
210 format = 2;
211 break;
212 }
213 }
214 u.format.set (format);
215 switch (u.format) {
216 case 1: return TRACE_RETURN (u.format1.serialize (c, glyphs, num_glyphs, delta));
217 case 2: return TRACE_RETURN (u.format2.serialize (c, glyphs, substitutes, num_glyphs));
218 default:return TRACE_RETURN (false);
219 }
220 }
222 template <typename context_t>
223 inline typename context_t::return_t dispatch (context_t *c) const
224 {
225 TRACE_DISPATCH (this);
226 switch (u.format) {
227 case 1: return TRACE_RETURN (c->dispatch (u.format1));
228 case 2: return TRACE_RETURN (c->dispatch (u.format2));
229 default:return TRACE_RETURN (c->default_return_value ());
230 }
231 }
233 inline bool sanitize (hb_sanitize_context_t *c) {
234 TRACE_SANITIZE (this);
235 if (!u.format.sanitize (c)) return TRACE_RETURN (false);
236 switch (u.format) {
237 case 1: return TRACE_RETURN (u.format1.sanitize (c));
238 case 2: return TRACE_RETURN (u.format2.sanitize (c));
239 default:return TRACE_RETURN (true);
240 }
241 }
243 protected:
244 union {
245 USHORT format; /* Format identifier */
246 SingleSubstFormat1 format1;
247 SingleSubstFormat2 format2;
248 } u;
249 };
252 struct Sequence
253 {
254 inline void closure (hb_closure_context_t *c) const
255 {
256 TRACE_CLOSURE (this);
257 unsigned int count = substitute.len;
258 for (unsigned int i = 0; i < count; i++)
259 c->glyphs->add (substitute[i]);
260 }
262 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
263 {
264 TRACE_COLLECT_GLYPHS (this);
265 unsigned int count = substitute.len;
266 for (unsigned int i = 0; i < count; i++)
267 c->output->add (substitute[i]);
268 }
270 inline bool apply (hb_apply_context_t *c) const
271 {
272 TRACE_APPLY (this);
273 if (unlikely (!substitute.len)) return TRACE_RETURN (false);
275 unsigned int klass = _hb_glyph_info_is_ligature (&c->buffer->cur()) ?
276 HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH : 0;
277 unsigned int count = substitute.len;
278 if (count == 1) /* Special-case to make it in-place. */
279 {
280 c->replace_glyph (substitute.array[0]);
281 }
282 else
283 {
284 for (unsigned int i = 0; i < count; i++) {
285 _hb_glyph_info_set_lig_props_for_component (&c->buffer->cur(), i);
286 c->output_glyph (substitute.array[i], klass);
287 }
288 c->buffer->skip_glyph ();
289 }
291 return TRACE_RETURN (true);
292 }
294 inline bool serialize (hb_serialize_context_t *c,
295 Supplier<GlyphID> &glyphs,
296 unsigned int num_glyphs)
297 {
298 TRACE_SERIALIZE (this);
299 if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
300 if (unlikely (!substitute.serialize (c, glyphs, num_glyphs))) return TRACE_RETURN (false);
301 return TRACE_RETURN (true);
302 }
304 inline bool sanitize (hb_sanitize_context_t *c) {
305 TRACE_SANITIZE (this);
306 return TRACE_RETURN (substitute.sanitize (c));
307 }
309 protected:
310 ArrayOf<GlyphID>
311 substitute; /* String of GlyphIDs to substitute */
312 public:
313 DEFINE_SIZE_ARRAY (2, substitute);
314 };
316 struct MultipleSubstFormat1
317 {
318 inline void closure (hb_closure_context_t *c) const
319 {
320 TRACE_CLOSURE (this);
321 Coverage::Iter iter;
322 for (iter.init (this+coverage); iter.more (); iter.next ()) {
323 if (c->glyphs->has (iter.get_glyph ()))
324 (this+sequence[iter.get_coverage ()]).closure (c);
325 }
326 }
328 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
329 {
330 TRACE_COLLECT_GLYPHS (this);
331 (this+coverage).add_coverage (c->input);
332 unsigned int count = sequence.len;
333 for (unsigned int i = 0; i < count; i++)
334 (this+sequence[i]).collect_glyphs (c);
335 }
337 inline const Coverage &get_coverage (void) const
338 {
339 return this+coverage;
340 }
342 inline bool would_apply (hb_would_apply_context_t *c) const
343 {
344 TRACE_WOULD_APPLY (this);
345 return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
346 }
348 inline bool apply (hb_apply_context_t *c) const
349 {
350 TRACE_APPLY (this);
352 unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);
353 if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
355 return TRACE_RETURN ((this+sequence[index]).apply (c));
356 }
358 inline bool serialize (hb_serialize_context_t *c,
359 Supplier<GlyphID> &glyphs,
360 Supplier<unsigned int> &substitute_len_list,
361 unsigned int num_glyphs,
362 Supplier<GlyphID> &substitute_glyphs_list)
363 {
364 TRACE_SERIALIZE (this);
365 if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
366 if (unlikely (!sequence.serialize (c, num_glyphs))) return TRACE_RETURN (false);
367 for (unsigned int i = 0; i < num_glyphs; i++)
368 if (unlikely (!sequence[i].serialize (c, this).serialize (c,
369 substitute_glyphs_list,
370 substitute_len_list[i]))) return TRACE_RETURN (false);
371 substitute_len_list.advance (num_glyphs);
372 if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return TRACE_RETURN (false);
373 return TRACE_RETURN (true);
374 }
376 inline bool sanitize (hb_sanitize_context_t *c) {
377 TRACE_SANITIZE (this);
378 return TRACE_RETURN (coverage.sanitize (c, this) && sequence.sanitize (c, this));
379 }
381 protected:
382 USHORT format; /* Format identifier--format = 1 */
383 OffsetTo<Coverage>
384 coverage; /* Offset to Coverage table--from
385 * beginning of Substitution table */
386 OffsetArrayOf<Sequence>
387 sequence; /* Array of Sequence tables
388 * ordered by Coverage Index */
389 public:
390 DEFINE_SIZE_ARRAY (6, sequence);
391 };
393 struct MultipleSubst
394 {
395 inline bool serialize (hb_serialize_context_t *c,
396 Supplier<GlyphID> &glyphs,
397 Supplier<unsigned int> &substitute_len_list,
398 unsigned int num_glyphs,
399 Supplier<GlyphID> &substitute_glyphs_list)
400 {
401 TRACE_SERIALIZE (this);
402 if (unlikely (!c->extend_min (u.format))) return TRACE_RETURN (false);
403 unsigned int format = 1;
404 u.format.set (format);
405 switch (u.format) {
406 case 1: return TRACE_RETURN (u.format1.serialize (c, glyphs, substitute_len_list, num_glyphs, substitute_glyphs_list));
407 default:return TRACE_RETURN (false);
408 }
409 }
411 template <typename context_t>
412 inline typename context_t::return_t dispatch (context_t *c) const
413 {
414 TRACE_DISPATCH (this);
415 switch (u.format) {
416 case 1: return TRACE_RETURN (c->dispatch (u.format1));
417 default:return TRACE_RETURN (c->default_return_value ());
418 }
419 }
421 inline bool sanitize (hb_sanitize_context_t *c) {
422 TRACE_SANITIZE (this);
423 if (!u.format.sanitize (c)) return TRACE_RETURN (false);
424 switch (u.format) {
425 case 1: return TRACE_RETURN (u.format1.sanitize (c));
426 default:return TRACE_RETURN (true);
427 }
428 }
430 protected:
431 union {
432 USHORT format; /* Format identifier */
433 MultipleSubstFormat1 format1;
434 } u;
435 };
438 typedef ArrayOf<GlyphID> AlternateSet; /* Array of alternate GlyphIDs--in
439 * arbitrary order */
441 struct AlternateSubstFormat1
442 {
443 inline void closure (hb_closure_context_t *c) const
444 {
445 TRACE_CLOSURE (this);
446 Coverage::Iter iter;
447 for (iter.init (this+coverage); iter.more (); iter.next ()) {
448 if (c->glyphs->has (iter.get_glyph ())) {
449 const AlternateSet &alt_set = this+alternateSet[iter.get_coverage ()];
450 unsigned int count = alt_set.len;
451 for (unsigned int i = 0; i < count; i++)
452 c->glyphs->add (alt_set[i]);
453 }
454 }
455 }
457 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
458 {
459 TRACE_COLLECT_GLYPHS (this);
460 Coverage::Iter iter;
461 for (iter.init (this+coverage); iter.more (); iter.next ()) {
462 c->input->add (iter.get_glyph ());
463 const AlternateSet &alt_set = this+alternateSet[iter.get_coverage ()];
464 unsigned int count = alt_set.len;
465 for (unsigned int i = 0; i < count; i++)
466 c->output->add (alt_set[i]);
467 }
468 }
470 inline const Coverage &get_coverage (void) const
471 {
472 return this+coverage;
473 }
475 inline bool would_apply (hb_would_apply_context_t *c) const
476 {
477 TRACE_WOULD_APPLY (this);
478 return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
479 }
481 inline bool apply (hb_apply_context_t *c) const
482 {
483 TRACE_APPLY (this);
484 hb_codepoint_t glyph_id = c->buffer->cur().codepoint;
486 unsigned int index = (this+coverage).get_coverage (glyph_id);
487 if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
489 const AlternateSet &alt_set = this+alternateSet[index];
491 if (unlikely (!alt_set.len)) return TRACE_RETURN (false);
493 hb_mask_t glyph_mask = c->buffer->cur().mask;
494 hb_mask_t lookup_mask = c->lookup_mask;
496 /* Note: This breaks badly if two features enabled this lookup together. */
497 unsigned int shift = _hb_ctz (lookup_mask);
498 unsigned int alt_index = ((lookup_mask & glyph_mask) >> shift);
500 if (unlikely (alt_index > alt_set.len || alt_index == 0)) return TRACE_RETURN (false);
502 glyph_id = alt_set[alt_index - 1];
504 c->replace_glyph (glyph_id);
506 return TRACE_RETURN (true);
507 }
509 inline bool serialize (hb_serialize_context_t *c,
510 Supplier<GlyphID> &glyphs,
511 Supplier<unsigned int> &alternate_len_list,
512 unsigned int num_glyphs,
513 Supplier<GlyphID> &alternate_glyphs_list)
514 {
515 TRACE_SERIALIZE (this);
516 if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
517 if (unlikely (!alternateSet.serialize (c, num_glyphs))) return TRACE_RETURN (false);
518 for (unsigned int i = 0; i < num_glyphs; i++)
519 if (unlikely (!alternateSet[i].serialize (c, this).serialize (c,
520 alternate_glyphs_list,
521 alternate_len_list[i]))) return TRACE_RETURN (false);
522 alternate_len_list.advance (num_glyphs);
523 if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return TRACE_RETURN (false);
524 return TRACE_RETURN (true);
525 }
527 inline bool sanitize (hb_sanitize_context_t *c) {
528 TRACE_SANITIZE (this);
529 return TRACE_RETURN (coverage.sanitize (c, this) && alternateSet.sanitize (c, this));
530 }
532 protected:
533 USHORT format; /* Format identifier--format = 1 */
534 OffsetTo<Coverage>
535 coverage; /* Offset to Coverage table--from
536 * beginning of Substitution table */
537 OffsetArrayOf<AlternateSet>
538 alternateSet; /* Array of AlternateSet tables
539 * ordered by Coverage Index */
540 public:
541 DEFINE_SIZE_ARRAY (6, alternateSet);
542 };
544 struct AlternateSubst
545 {
546 inline bool serialize (hb_serialize_context_t *c,
547 Supplier<GlyphID> &glyphs,
548 Supplier<unsigned int> &alternate_len_list,
549 unsigned int num_glyphs,
550 Supplier<GlyphID> &alternate_glyphs_list)
551 {
552 TRACE_SERIALIZE (this);
553 if (unlikely (!c->extend_min (u.format))) return TRACE_RETURN (false);
554 unsigned int format = 1;
555 u.format.set (format);
556 switch (u.format) {
557 case 1: return TRACE_RETURN (u.format1.serialize (c, glyphs, alternate_len_list, num_glyphs, alternate_glyphs_list));
558 default:return TRACE_RETURN (false);
559 }
560 }
562 template <typename context_t>
563 inline typename context_t::return_t dispatch (context_t *c) const
564 {
565 TRACE_DISPATCH (this);
566 switch (u.format) {
567 case 1: return TRACE_RETURN (c->dispatch (u.format1));
568 default:return TRACE_RETURN (c->default_return_value ());
569 }
570 }
572 inline bool sanitize (hb_sanitize_context_t *c) {
573 TRACE_SANITIZE (this);
574 if (!u.format.sanitize (c)) return TRACE_RETURN (false);
575 switch (u.format) {
576 case 1: return TRACE_RETURN (u.format1.sanitize (c));
577 default:return TRACE_RETURN (true);
578 }
579 }
581 protected:
582 union {
583 USHORT format; /* Format identifier */
584 AlternateSubstFormat1 format1;
585 } u;
586 };
589 struct Ligature
590 {
591 inline void closure (hb_closure_context_t *c) const
592 {
593 TRACE_CLOSURE (this);
594 unsigned int count = component.len;
595 for (unsigned int i = 1; i < count; i++)
596 if (!c->glyphs->has (component[i]))
597 return;
598 c->glyphs->add (ligGlyph);
599 }
601 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
602 {
603 TRACE_COLLECT_GLYPHS (this);
604 unsigned int count = component.len;
605 for (unsigned int i = 1; i < count; i++)
606 c->input->add (component[i]);
607 c->output->add (ligGlyph);
608 }
610 inline bool would_apply (hb_would_apply_context_t *c) const
611 {
612 TRACE_WOULD_APPLY (this);
613 if (c->len != component.len)
614 return TRACE_RETURN (false);
616 for (unsigned int i = 1; i < c->len; i++)
617 if (likely (c->glyphs[i] != component[i]))
618 return TRACE_RETURN (false);
620 return TRACE_RETURN (true);
621 }
623 inline bool apply (hb_apply_context_t *c) const
624 {
625 TRACE_APPLY (this);
626 unsigned int count = component.len;
627 if (unlikely (count < 1)) return TRACE_RETURN (false);
629 bool is_mark_ligature = false;
630 unsigned int total_component_count = 0;
632 unsigned int match_length = 0;
633 unsigned int match_positions[MAX_CONTEXT_LENGTH];
635 if (likely (!match_input (c, count,
636 &component[1],
637 match_glyph,
638 NULL,
639 &match_length,
640 match_positions,
641 &is_mark_ligature,
642 &total_component_count)))
643 return TRACE_RETURN (false);
645 ligate_input (c,
646 count,
647 match_positions,
648 match_length,
649 ligGlyph,
650 is_mark_ligature,
651 total_component_count);
653 return TRACE_RETURN (true);
654 }
656 inline bool serialize (hb_serialize_context_t *c,
657 GlyphID ligature,
658 Supplier<GlyphID> &components, /* Starting from second */
659 unsigned int num_components /* Including first component */)
660 {
661 TRACE_SERIALIZE (this);
662 if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
663 ligGlyph = ligature;
664 if (unlikely (!component.serialize (c, components, num_components))) return TRACE_RETURN (false);
665 return TRACE_RETURN (true);
666 }
668 public:
669 inline bool sanitize (hb_sanitize_context_t *c) {
670 TRACE_SANITIZE (this);
671 return TRACE_RETURN (ligGlyph.sanitize (c) && component.sanitize (c));
672 }
674 protected:
675 GlyphID ligGlyph; /* GlyphID of ligature to substitute */
676 HeadlessArrayOf<GlyphID>
677 component; /* Array of component GlyphIDs--start
678 * with the second component--ordered
679 * in writing direction */
680 public:
681 DEFINE_SIZE_ARRAY (4, component);
682 };
684 struct LigatureSet
685 {
686 inline void closure (hb_closure_context_t *c) const
687 {
688 TRACE_CLOSURE (this);
689 unsigned int num_ligs = ligature.len;
690 for (unsigned int i = 0; i < num_ligs; i++)
691 (this+ligature[i]).closure (c);
692 }
694 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
695 {
696 TRACE_COLLECT_GLYPHS (this);
697 unsigned int num_ligs = ligature.len;
698 for (unsigned int i = 0; i < num_ligs; i++)
699 (this+ligature[i]).collect_glyphs (c);
700 }
702 inline bool would_apply (hb_would_apply_context_t *c) const
703 {
704 TRACE_WOULD_APPLY (this);
705 unsigned int num_ligs = ligature.len;
706 for (unsigned int i = 0; i < num_ligs; i++)
707 {
708 const Ligature &lig = this+ligature[i];
709 if (lig.would_apply (c))
710 return TRACE_RETURN (true);
711 }
712 return TRACE_RETURN (false);
713 }
715 inline bool apply (hb_apply_context_t *c) const
716 {
717 TRACE_APPLY (this);
718 unsigned int num_ligs = ligature.len;
719 for (unsigned int i = 0; i < num_ligs; i++)
720 {
721 const Ligature &lig = this+ligature[i];
722 if (lig.apply (c)) return TRACE_RETURN (true);
723 }
725 return TRACE_RETURN (false);
726 }
728 inline bool serialize (hb_serialize_context_t *c,
729 Supplier<GlyphID> &ligatures,
730 Supplier<unsigned int> &component_count_list,
731 unsigned int num_ligatures,
732 Supplier<GlyphID> &component_list /* Starting from second for each ligature */)
733 {
734 TRACE_SERIALIZE (this);
735 if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
736 if (unlikely (!ligature.serialize (c, num_ligatures))) return TRACE_RETURN (false);
737 for (unsigned int i = 0; i < num_ligatures; i++)
738 if (unlikely (!ligature[i].serialize (c, this).serialize (c,
739 ligatures[i],
740 component_list,
741 component_count_list[i]))) return TRACE_RETURN (false);
742 ligatures.advance (num_ligatures);
743 component_count_list.advance (num_ligatures);
744 return TRACE_RETURN (true);
745 }
747 inline bool sanitize (hb_sanitize_context_t *c) {
748 TRACE_SANITIZE (this);
749 return TRACE_RETURN (ligature.sanitize (c, this));
750 }
752 protected:
753 OffsetArrayOf<Ligature>
754 ligature; /* Array LigatureSet tables
755 * ordered by preference */
756 public:
757 DEFINE_SIZE_ARRAY (2, ligature);
758 };
760 struct LigatureSubstFormat1
761 {
762 inline void closure (hb_closure_context_t *c) const
763 {
764 TRACE_CLOSURE (this);
765 Coverage::Iter iter;
766 for (iter.init (this+coverage); iter.more (); iter.next ()) {
767 if (c->glyphs->has (iter.get_glyph ()))
768 (this+ligatureSet[iter.get_coverage ()]).closure (c);
769 }
770 }
772 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
773 {
774 TRACE_COLLECT_GLYPHS (this);
775 Coverage::Iter iter;
776 for (iter.init (this+coverage); iter.more (); iter.next ()) {
777 c->input->add (iter.get_glyph ());
778 (this+ligatureSet[iter.get_coverage ()]).collect_glyphs (c);
779 }
780 }
782 inline const Coverage &get_coverage (void) const
783 {
784 return this+coverage;
785 }
787 inline bool would_apply (hb_would_apply_context_t *c) const
788 {
789 TRACE_WOULD_APPLY (this);
790 unsigned int index = (this+coverage).get_coverage (c->glyphs[0]);
791 if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
793 const LigatureSet &lig_set = this+ligatureSet[index];
794 return TRACE_RETURN (lig_set.would_apply (c));
795 }
797 inline bool apply (hb_apply_context_t *c) const
798 {
799 TRACE_APPLY (this);
800 hb_codepoint_t glyph_id = c->buffer->cur().codepoint;
802 unsigned int index = (this+coverage).get_coverage (glyph_id);
803 if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
805 const LigatureSet &lig_set = this+ligatureSet[index];
806 return TRACE_RETURN (lig_set.apply (c));
807 }
809 inline bool serialize (hb_serialize_context_t *c,
810 Supplier<GlyphID> &first_glyphs,
811 Supplier<unsigned int> &ligature_per_first_glyph_count_list,
812 unsigned int num_first_glyphs,
813 Supplier<GlyphID> &ligatures_list,
814 Supplier<unsigned int> &component_count_list,
815 Supplier<GlyphID> &component_list /* Starting from second for each ligature */)
816 {
817 TRACE_SERIALIZE (this);
818 if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
819 if (unlikely (!ligatureSet.serialize (c, num_first_glyphs))) return TRACE_RETURN (false);
820 for (unsigned int i = 0; i < num_first_glyphs; i++)
821 if (unlikely (!ligatureSet[i].serialize (c, this).serialize (c,
822 ligatures_list,
823 component_count_list,
824 ligature_per_first_glyph_count_list[i],
825 component_list))) return TRACE_RETURN (false);
826 ligature_per_first_glyph_count_list.advance (num_first_glyphs);
827 if (unlikely (!coverage.serialize (c, this).serialize (c, first_glyphs, num_first_glyphs))) return TRACE_RETURN (false);
828 return TRACE_RETURN (true);
829 }
831 inline bool sanitize (hb_sanitize_context_t *c) {
832 TRACE_SANITIZE (this);
833 return TRACE_RETURN (coverage.sanitize (c, this) && ligatureSet.sanitize (c, this));
834 }
836 protected:
837 USHORT format; /* Format identifier--format = 1 */
838 OffsetTo<Coverage>
839 coverage; /* Offset to Coverage table--from
840 * beginning of Substitution table */
841 OffsetArrayOf<LigatureSet>
842 ligatureSet; /* Array LigatureSet tables
843 * ordered by Coverage Index */
844 public:
845 DEFINE_SIZE_ARRAY (6, ligatureSet);
846 };
848 struct LigatureSubst
849 {
850 inline bool serialize (hb_serialize_context_t *c,
851 Supplier<GlyphID> &first_glyphs,
852 Supplier<unsigned int> &ligature_per_first_glyph_count_list,
853 unsigned int num_first_glyphs,
854 Supplier<GlyphID> &ligatures_list,
855 Supplier<unsigned int> &component_count_list,
856 Supplier<GlyphID> &component_list /* Starting from second for each ligature */)
857 {
858 TRACE_SERIALIZE (this);
859 if (unlikely (!c->extend_min (u.format))) return TRACE_RETURN (false);
860 unsigned int format = 1;
861 u.format.set (format);
862 switch (u.format) {
863 case 1: return TRACE_RETURN (u.format1.serialize (c, first_glyphs, ligature_per_first_glyph_count_list, num_first_glyphs,
864 ligatures_list, component_count_list, component_list));
865 default:return TRACE_RETURN (false);
866 }
867 }
869 template <typename context_t>
870 inline typename context_t::return_t dispatch (context_t *c) const
871 {
872 TRACE_DISPATCH (this);
873 switch (u.format) {
874 case 1: return TRACE_RETURN (c->dispatch (u.format1));
875 default:return TRACE_RETURN (c->default_return_value ());
876 }
877 }
879 inline bool sanitize (hb_sanitize_context_t *c) {
880 TRACE_SANITIZE (this);
881 if (!u.format.sanitize (c)) return TRACE_RETURN (false);
882 switch (u.format) {
883 case 1: return TRACE_RETURN (u.format1.sanitize (c));
884 default:return TRACE_RETURN (true);
885 }
886 }
888 protected:
889 union {
890 USHORT format; /* Format identifier */
891 LigatureSubstFormat1 format1;
892 } u;
893 };
896 struct ContextSubst : Context {};
898 struct ChainContextSubst : ChainContext {};
900 struct ExtensionSubst : Extension<ExtensionSubst>
901 {
902 typedef struct SubstLookupSubTable LookupSubTable;
904 inline bool is_reverse (void) const;
905 };
908 struct ReverseChainSingleSubstFormat1
909 {
910 inline void closure (hb_closure_context_t *c) const
911 {
912 TRACE_CLOSURE (this);
913 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
915 unsigned int count;
917 count = backtrack.len;
918 for (unsigned int i = 0; i < count; i++)
919 if (!(this+backtrack[i]).intersects (c->glyphs))
920 return;
922 count = lookahead.len;
923 for (unsigned int i = 0; i < count; i++)
924 if (!(this+lookahead[i]).intersects (c->glyphs))
925 return;
927 const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
928 Coverage::Iter iter;
929 for (iter.init (this+coverage); iter.more (); iter.next ()) {
930 if (c->glyphs->has (iter.get_glyph ()))
931 c->glyphs->add (substitute[iter.get_coverage ()]);
932 }
933 }
935 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const
936 {
937 TRACE_COLLECT_GLYPHS (this);
939 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
941 unsigned int count;
943 (this+coverage).add_coverage (c->input);
945 count = backtrack.len;
946 for (unsigned int i = 0; i < count; i++)
947 (this+backtrack[i]).add_coverage (c->before);
949 count = lookahead.len;
950 for (unsigned int i = 0; i < count; i++)
951 (this+lookahead[i]).add_coverage (c->after);
953 const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
954 count = substitute.len;
955 for (unsigned int i = 0; i < count; i++)
956 c->output->add (substitute[i]);
957 }
959 inline const Coverage &get_coverage (void) const
960 {
961 return this+coverage;
962 }
964 inline bool would_apply (hb_would_apply_context_t *c) const
965 {
966 TRACE_WOULD_APPLY (this);
967 return TRACE_RETURN (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED);
968 }
970 inline bool apply (hb_apply_context_t *c) const
971 {
972 TRACE_APPLY (this);
973 if (unlikely (c->nesting_level_left != MAX_NESTING_LEVEL))
974 return TRACE_RETURN (false); /* No chaining to this type */
976 unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);
977 if (likely (index == NOT_COVERED)) return TRACE_RETURN (false);
979 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
980 const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
982 if (match_backtrack (c,
983 backtrack.len, (USHORT *) backtrack.array,
984 match_coverage, this) &&
985 match_lookahead (c,
986 lookahead.len, (USHORT *) lookahead.array,
987 match_coverage, this,
988 1))
989 {
990 c->replace_glyph_inplace (substitute[index]);
991 /* Note: We DON'T decrease buffer->idx. The main loop does it
992 * for us. This is useful for preventing surprises if someone
993 * calls us through a Context lookup. */
994 return TRACE_RETURN (true);
995 }
997 return TRACE_RETURN (false);
998 }
1000 inline bool sanitize (hb_sanitize_context_t *c) {
1001 TRACE_SANITIZE (this);
1002 if (!(coverage.sanitize (c, this) && backtrack.sanitize (c, this)))
1003 return TRACE_RETURN (false);
1004 OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
1005 if (!lookahead.sanitize (c, this))
1006 return TRACE_RETURN (false);
1007 ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
1008 return TRACE_RETURN (substitute.sanitize (c));
1009 }
1011 protected:
1012 USHORT format; /* Format identifier--format = 1 */
1013 OffsetTo<Coverage>
1014 coverage; /* Offset to Coverage table--from
1015 * beginning of table */
1016 OffsetArrayOf<Coverage>
1017 backtrack; /* Array of coverage tables
1018 * in backtracking sequence, in glyph
1019 * sequence order */
1020 OffsetArrayOf<Coverage>
1021 lookaheadX; /* Array of coverage tables
1022 * in lookahead sequence, in glyph
1023 * sequence order */
1024 ArrayOf<GlyphID>
1025 substituteX; /* Array of substitute
1026 * GlyphIDs--ordered by Coverage Index */
1027 public:
1028 DEFINE_SIZE_MIN (10);
1029 };
1031 struct ReverseChainSingleSubst
1032 {
1033 template <typename context_t>
1034 inline typename context_t::return_t dispatch (context_t *c) const
1035 {
1036 TRACE_DISPATCH (this);
1037 switch (u.format) {
1038 case 1: return TRACE_RETURN (c->dispatch (u.format1));
1039 default:return TRACE_RETURN (c->default_return_value ());
1040 }
1041 }
1043 inline bool sanitize (hb_sanitize_context_t *c) {
1044 TRACE_SANITIZE (this);
1045 if (!u.format.sanitize (c)) return TRACE_RETURN (false);
1046 switch (u.format) {
1047 case 1: return TRACE_RETURN (u.format1.sanitize (c));
1048 default:return TRACE_RETURN (true);
1049 }
1050 }
1052 protected:
1053 union {
1054 USHORT format; /* Format identifier */
1055 ReverseChainSingleSubstFormat1 format1;
1056 } u;
1057 };
1061 /*
1062 * SubstLookup
1063 */
1065 struct SubstLookupSubTable
1066 {
1067 friend struct SubstLookup;
1069 enum Type {
1070 Single = 1,
1071 Multiple = 2,
1072 Alternate = 3,
1073 Ligature = 4,
1074 Context = 5,
1075 ChainContext = 6,
1076 Extension = 7,
1077 ReverseChainSingle = 8
1078 };
1080 template <typename context_t>
1081 inline typename context_t::return_t dispatch (context_t *c, unsigned int lookup_type) const
1082 {
1083 TRACE_DISPATCH (this);
1084 switch (lookup_type) {
1085 case Single: return TRACE_RETURN (u.single.dispatch (c));
1086 case Multiple: return TRACE_RETURN (u.multiple.dispatch (c));
1087 case Alternate: return TRACE_RETURN (u.alternate.dispatch (c));
1088 case Ligature: return TRACE_RETURN (u.ligature.dispatch (c));
1089 case Context: return TRACE_RETURN (u.context.dispatch (c));
1090 case ChainContext: return TRACE_RETURN (u.chainContext.dispatch (c));
1091 case Extension: return TRACE_RETURN (u.extension.dispatch (c));
1092 case ReverseChainSingle: return TRACE_RETURN (u.reverseChainContextSingle.dispatch (c));
1093 default: return TRACE_RETURN (c->default_return_value ());
1094 }
1095 }
1097 inline bool sanitize (hb_sanitize_context_t *c, unsigned int lookup_type) {
1098 TRACE_SANITIZE (this);
1099 if (!u.header.sub_format.sanitize (c))
1100 return TRACE_RETURN (false);
1101 switch (lookup_type) {
1102 case Single: return TRACE_RETURN (u.single.sanitize (c));
1103 case Multiple: return TRACE_RETURN (u.multiple.sanitize (c));
1104 case Alternate: return TRACE_RETURN (u.alternate.sanitize (c));
1105 case Ligature: return TRACE_RETURN (u.ligature.sanitize (c));
1106 case Context: return TRACE_RETURN (u.context.sanitize (c));
1107 case ChainContext: return TRACE_RETURN (u.chainContext.sanitize (c));
1108 case Extension: return TRACE_RETURN (u.extension.sanitize (c));
1109 case ReverseChainSingle: return TRACE_RETURN (u.reverseChainContextSingle.sanitize (c));
1110 default: return TRACE_RETURN (true);
1111 }
1112 }
1114 protected:
1115 union {
1116 struct {
1117 USHORT sub_format;
1118 } header;
1119 SingleSubst single;
1120 MultipleSubst multiple;
1121 AlternateSubst alternate;
1122 LigatureSubst ligature;
1123 ContextSubst context;
1124 ChainContextSubst chainContext;
1125 ExtensionSubst extension;
1126 ReverseChainSingleSubst reverseChainContextSingle;
1127 } u;
1128 public:
1129 DEFINE_SIZE_UNION (2, header.sub_format);
1130 };
1133 struct SubstLookup : Lookup
1134 {
1135 inline const SubstLookupSubTable& get_subtable (unsigned int i) const
1136 { return this+CastR<OffsetArrayOf<SubstLookupSubTable> > (subTable)[i]; }
1138 inline static bool lookup_type_is_reverse (unsigned int lookup_type)
1139 { return lookup_type == SubstLookupSubTable::ReverseChainSingle; }
1141 inline bool is_reverse (void) const
1142 {
1143 unsigned int type = get_type ();
1144 if (unlikely (type == SubstLookupSubTable::Extension))
1145 return CastR<ExtensionSubst> (get_subtable(0)).is_reverse ();
1146 return lookup_type_is_reverse (type);
1147 }
1149 inline hb_closure_context_t::return_t closure (hb_closure_context_t *c) const
1150 {
1151 TRACE_CLOSURE (this);
1152 c->set_recurse_func (dispatch_recurse_func<hb_closure_context_t>);
1153 return TRACE_RETURN (dispatch (c));
1154 }
1156 inline hb_collect_glyphs_context_t::return_t collect_glyphs (hb_collect_glyphs_context_t *c) const
1157 {
1158 TRACE_COLLECT_GLYPHS (this);
1159 c->set_recurse_func (dispatch_recurse_func<hb_collect_glyphs_context_t>);
1160 return TRACE_RETURN (dispatch (c));
1161 }
1163 template <typename set_t>
1164 inline void add_coverage (set_t *glyphs) const
1165 {
1166 hb_get_coverage_context_t c;
1167 const Coverage *last = NULL;
1168 unsigned int count = get_subtable_count ();
1169 for (unsigned int i = 0; i < count; i++) {
1170 const Coverage *coverage = &get_subtable (i).dispatch (&c, get_type ());
1171 if (coverage != last) {
1172 coverage->add_coverage (glyphs);
1173 last = coverage;
1174 }
1175 }
1176 }
1178 inline bool would_apply (hb_would_apply_context_t *c, const hb_set_digest_t *digest) const
1179 {
1180 TRACE_WOULD_APPLY (this);
1181 if (unlikely (!c->len)) return TRACE_RETURN (false);
1182 if (!digest->may_have (c->glyphs[0])) return TRACE_RETURN (false);
1183 return TRACE_RETURN (dispatch (c));
1184 }
1186 inline bool apply_once (hb_apply_context_t *c) const
1187 {
1188 TRACE_APPLY (this);
1189 if (!c->check_glyph_property (&c->buffer->cur(), c->lookup_props))
1190 return TRACE_RETURN (false);
1191 return TRACE_RETURN (dispatch (c));
1192 }
1194 static bool apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index);
1196 inline SubstLookupSubTable& serialize_subtable (hb_serialize_context_t *c,
1197 unsigned int i)
1198 { return CastR<OffsetArrayOf<SubstLookupSubTable> > (subTable)[i].serialize (c, this); }
1200 inline bool serialize_single (hb_serialize_context_t *c,
1201 uint32_t lookup_props,
1202 Supplier<GlyphID> &glyphs,
1203 Supplier<GlyphID> &substitutes,
1204 unsigned int num_glyphs)
1205 {
1206 TRACE_SERIALIZE (this);
1207 if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Single, lookup_props, 1))) return TRACE_RETURN (false);
1208 return TRACE_RETURN (serialize_subtable (c, 0).u.single.serialize (c, glyphs, substitutes, num_glyphs));
1209 }
1211 inline bool serialize_multiple (hb_serialize_context_t *c,
1212 uint32_t lookup_props,
1213 Supplier<GlyphID> &glyphs,
1214 Supplier<unsigned int> &substitute_len_list,
1215 unsigned int num_glyphs,
1216 Supplier<GlyphID> &substitute_glyphs_list)
1217 {
1218 TRACE_SERIALIZE (this);
1219 if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Multiple, lookup_props, 1))) return TRACE_RETURN (false);
1220 return TRACE_RETURN (serialize_subtable (c, 0).u.multiple.serialize (c, glyphs, substitute_len_list, num_glyphs,
1221 substitute_glyphs_list));
1222 }
1224 inline bool serialize_alternate (hb_serialize_context_t *c,
1225 uint32_t lookup_props,
1226 Supplier<GlyphID> &glyphs,
1227 Supplier<unsigned int> &alternate_len_list,
1228 unsigned int num_glyphs,
1229 Supplier<GlyphID> &alternate_glyphs_list)
1230 {
1231 TRACE_SERIALIZE (this);
1232 if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Alternate, lookup_props, 1))) return TRACE_RETURN (false);
1233 return TRACE_RETURN (serialize_subtable (c, 0).u.alternate.serialize (c, glyphs, alternate_len_list, num_glyphs,
1234 alternate_glyphs_list));
1235 }
1237 inline bool serialize_ligature (hb_serialize_context_t *c,
1238 uint32_t lookup_props,
1239 Supplier<GlyphID> &first_glyphs,
1240 Supplier<unsigned int> &ligature_per_first_glyph_count_list,
1241 unsigned int num_first_glyphs,
1242 Supplier<GlyphID> &ligatures_list,
1243 Supplier<unsigned int> &component_count_list,
1244 Supplier<GlyphID> &component_list /* Starting from second for each ligature */)
1245 {
1246 TRACE_SERIALIZE (this);
1247 if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Ligature, lookup_props, 1))) return TRACE_RETURN (false);
1248 return TRACE_RETURN (serialize_subtable (c, 0).u.ligature.serialize (c, first_glyphs, ligature_per_first_glyph_count_list, num_first_glyphs,
1249 ligatures_list, component_count_list, component_list));
1250 }
1252 template <typename context_t>
1253 static inline typename context_t::return_t dispatch_recurse_func (context_t *c, unsigned int lookup_index);
1255 template <typename context_t>
1256 inline typename context_t::return_t dispatch (context_t *c) const
1257 {
1258 TRACE_DISPATCH (this);
1259 unsigned int lookup_type = get_type ();
1260 unsigned int count = get_subtable_count ();
1261 for (unsigned int i = 0; i < count; i++) {
1262 typename context_t::return_t r = get_subtable (i).dispatch (c, lookup_type);
1263 if (c->stop_sublookup_iteration (r))
1264 return TRACE_RETURN (r);
1265 }
1266 return TRACE_RETURN (c->default_return_value ());
1267 }
1269 inline bool sanitize (hb_sanitize_context_t *c)
1270 {
1271 TRACE_SANITIZE (this);
1272 if (unlikely (!Lookup::sanitize (c))) return TRACE_RETURN (false);
1273 OffsetArrayOf<SubstLookupSubTable> &list = CastR<OffsetArrayOf<SubstLookupSubTable> > (subTable);
1274 if (unlikely (!list.sanitize (c, this, get_type ()))) return TRACE_RETURN (false);
1276 if (unlikely (get_type () == SubstLookupSubTable::Extension))
1277 {
1278 /* The spec says all subtables of an Extension lookup should
1279 * have the same type. This is specially important if one has
1280 * a reverse type! */
1281 unsigned int type = get_subtable (0).u.extension.get_type ();
1282 unsigned int count = get_subtable_count ();
1283 for (unsigned int i = 1; i < count; i++)
1284 if (get_subtable (i).u.extension.get_type () != type)
1285 return TRACE_RETURN (false);
1286 }
1287 return TRACE_RETURN (true);
1288 }
1289 };
1291 typedef OffsetListOf<SubstLookup> SubstLookupList;
1293 /*
1294 * GSUB -- The Glyph Substitution Table
1295 */
1297 struct GSUB : GSUBGPOS
1298 {
1299 static const hb_tag_t tableTag = HB_OT_TAG_GSUB;
1301 inline const SubstLookup& get_lookup (unsigned int i) const
1302 { return CastR<SubstLookup> (GSUBGPOS::get_lookup (i)); }
1304 static inline void substitute_start (hb_font_t *font, hb_buffer_t *buffer);
1305 static inline void substitute_finish (hb_font_t *font, hb_buffer_t *buffer);
1307 inline bool sanitize (hb_sanitize_context_t *c) {
1308 TRACE_SANITIZE (this);
1309 if (unlikely (!GSUBGPOS::sanitize (c))) return TRACE_RETURN (false);
1310 OffsetTo<SubstLookupList> &list = CastR<OffsetTo<SubstLookupList> > (lookupList);
1311 return TRACE_RETURN (list.sanitize (c, this));
1312 }
1313 public:
1314 DEFINE_SIZE_STATIC (10);
1315 };
1318 void
1319 GSUB::substitute_start (hb_font_t *font, hb_buffer_t *buffer)
1320 {
1321 _hb_buffer_allocate_gsubgpos_vars (buffer);
1323 const GDEF &gdef = *hb_ot_layout_from_face (font->face)->gdef;
1324 unsigned int count = buffer->len;
1325 for (unsigned int i = 0; i < count; i++)
1326 {
1327 _hb_glyph_info_set_glyph_props (&buffer->info[i], gdef.get_glyph_props (buffer->info[i].codepoint));
1328 _hb_glyph_info_clear_lig_props (&buffer->info[i]);
1329 buffer->info[i].syllable() = 0;
1330 }
1331 }
1333 void
1334 GSUB::substitute_finish (hb_font_t *font HB_UNUSED, hb_buffer_t *buffer HB_UNUSED)
1335 {
1336 }
1339 /* Out-of-class implementation for methods recursing */
1341 inline bool ExtensionSubst::is_reverse (void) const
1342 {
1343 unsigned int type = get_type ();
1344 if (unlikely (type == SubstLookupSubTable::Extension))
1345 return CastR<ExtensionSubst> (get_subtable<SubstLookupSubTable>()).is_reverse ();
1346 return SubstLookup::lookup_type_is_reverse (type);
1347 }
1349 template <typename context_t>
1350 inline typename context_t::return_t SubstLookup::dispatch_recurse_func (context_t *c, unsigned int lookup_index)
1351 {
1352 const GSUB &gsub = *(hb_ot_layout_from_face (c->face)->gsub);
1353 const SubstLookup &l = gsub.get_lookup (lookup_index);
1354 return l.dispatch (c);
1355 }
1357 inline bool SubstLookup::apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index)
1358 {
1359 const GSUB &gsub = *(hb_ot_layout_from_face (c->face)->gsub);
1360 const SubstLookup &l = gsub.get_lookup (lookup_index);
1361 unsigned int saved_lookup_props = c->lookup_props;
1362 c->set_lookup (l);
1363 bool ret = l.apply_once (c);
1364 c->lookup_props = saved_lookup_props;
1365 return ret;
1366 }
1369 } /* namespace OT */
1372 #endif /* HB_OT_LAYOUT_GSUB_TABLE_HH */