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 */ 28 29 #ifndef HB_OT_LAYOUT_GSUB_TABLE_HH 30 #define HB_OT_LAYOUT_GSUB_TABLE_HH 31 32 #include "hb-ot-layout-gsubgpos-private.hh" 33 34 35 namespace OT { 36 37 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 { 46 /* TODO Switch to range-based API to work around malicious fonts. 47 * https://github.com/behdad/harfbuzz/issues/363 */ 48 hb_codepoint_t glyph_id = iter.get_glyph (); 49 if (c->glyphs->has (glyph_id)) 50 c->glyphs->add ((glyph_id + deltaGlyphID) & 0xFFFFu); 51 } 52 } 53 54 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 55 { 56 TRACE_COLLECT_GLYPHS (this); 57 Coverage::Iter iter; 58 for (iter.init (this+coverage); iter.more (); iter.next ()) 59 { 60 /* TODO Switch to range-based API to work around malicious fonts. 61 * https://github.com/behdad/harfbuzz/issues/363 */ 62 hb_codepoint_t glyph_id = iter.get_glyph (); 63 c->input->add (glyph_id); 64 c->output->add ((glyph_id + deltaGlyphID) & 0xFFFFu); 65 } 66 } 67 68 inline const Coverage &get_coverage (void) const 69 { 70 return this+coverage; 71 } 72 73 inline bool would_apply (hb_would_apply_context_t *c) const 74 { 75 TRACE_WOULD_APPLY (this); 76 return_trace (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED); 77 } 78 79 inline bool apply (hb_apply_context_t *c) const 80 { 81 TRACE_APPLY (this); 82 hb_codepoint_t glyph_id = c->buffer->cur().codepoint; 83 unsigned int index = (this+coverage).get_coverage (glyph_id); 84 if (likely (index == NOT_COVERED)) return_trace (false); 85 86 /* According to the Adobe Annotated OpenType Suite, result is always 87 * limited to 16bit. */ 88 glyph_id = (glyph_id + deltaGlyphID) & 0xFFFFu; 89 c->replace_glyph (glyph_id); 90 91 return_trace (true); 92 } 93 94 inline bool serialize (hb_serialize_context_t *c, 95 Supplier<GlyphID> &glyphs, 96 unsigned int num_glyphs, 97 int delta) 98 { 99 TRACE_SERIALIZE (this); 100 if (unlikely (!c->extend_min (*this))) return_trace (false); 101 if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return_trace (false); 102 deltaGlyphID.set (delta); /* TODO(serilaize) overflow? */ 103 return_trace (true); 104 } 105 106 inline bool sanitize (hb_sanitize_context_t *c) const 107 { 108 TRACE_SANITIZE (this); 109 return_trace (coverage.sanitize (c, this) && deltaGlyphID.sanitize (c)); 110 } 111 112 protected: 113 USHORT format; /* Format identifier--format = 1 */ 114 OffsetTo<Coverage> 115 coverage; /* Offset to Coverage table--from 116 * beginning of Substitution table */ 117 SHORT deltaGlyphID; /* Add to original GlyphID to get 118 * substitute GlyphID */ 119 public: 120 DEFINE_SIZE_STATIC (6); 121 }; 122 123 struct SingleSubstFormat2 124 { 125 inline void closure (hb_closure_context_t *c) const 126 { 127 TRACE_CLOSURE (this); 128 Coverage::Iter iter; 129 unsigned int count = substitute.len; 130 for (iter.init (this+coverage); iter.more (); iter.next ()) 131 { 132 if (unlikely (iter.get_coverage () >= count)) 133 break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ 134 if (c->glyphs->has (iter.get_glyph ())) 135 c->glyphs->add (substitute[iter.get_coverage ()]); 136 } 137 } 138 139 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 140 { 141 TRACE_COLLECT_GLYPHS (this); 142 Coverage::Iter iter; 143 unsigned int count = substitute.len; 144 for (iter.init (this+coverage); iter.more (); iter.next ()) 145 { 146 if (unlikely (iter.get_coverage () >= count)) 147 break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ 148 c->input->add (iter.get_glyph ()); 149 c->output->add (substitute[iter.get_coverage ()]); 150 } 151 } 152 153 inline const Coverage &get_coverage (void) const 154 { 155 return this+coverage; 156 } 157 158 inline bool would_apply (hb_would_apply_context_t *c) const 159 { 160 TRACE_WOULD_APPLY (this); 161 return_trace (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED); 162 } 163 164 inline bool apply (hb_apply_context_t *c) const 165 { 166 TRACE_APPLY (this); 167 hb_codepoint_t glyph_id = c->buffer->cur().codepoint; 168 unsigned int index = (this+coverage).get_coverage (glyph_id); 169 if (likely (index == NOT_COVERED)) return_trace (false); 170 171 if (unlikely (index >= substitute.len)) return_trace (false); 172 173 glyph_id = substitute[index]; 174 c->replace_glyph (glyph_id); 175 176 return_trace (true); 177 } 178 179 inline bool serialize (hb_serialize_context_t *c, 180 Supplier<GlyphID> &glyphs, 181 Supplier<GlyphID> &substitutes, 182 unsigned int num_glyphs) 183 { 184 TRACE_SERIALIZE (this); 185 if (unlikely (!c->extend_min (*this))) return_trace (false); 186 if (unlikely (!substitute.serialize (c, substitutes, num_glyphs))) return_trace (false); 187 if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return_trace (false); 188 return_trace (true); 189 } 190 191 inline bool sanitize (hb_sanitize_context_t *c) const 192 { 193 TRACE_SANITIZE (this); 194 return_trace (coverage.sanitize (c, this) && substitute.sanitize (c)); 195 } 196 197 protected: 198 USHORT format; /* Format identifier--format = 2 */ 199 OffsetTo<Coverage> 200 coverage; /* Offset to Coverage table--from 201 * beginning of Substitution table */ 202 ArrayOf<GlyphID> 203 substitute; /* Array of substitute 204 * GlyphIDs--ordered by Coverage Index */ 205 public: 206 DEFINE_SIZE_ARRAY (6, substitute); 207 }; 208 209 struct SingleSubst 210 { 211 inline bool serialize (hb_serialize_context_t *c, 212 Supplier<GlyphID> &glyphs, 213 Supplier<GlyphID> &substitutes, 214 unsigned int num_glyphs) 215 { 216 TRACE_SERIALIZE (this); 217 if (unlikely (!c->extend_min (u.format))) return_trace (false); 218 unsigned int format = 2; 219 int delta = 0; 220 if (num_glyphs) { 221 format = 1; 222 /* TODO(serialize) check for wrap-around */ 223 delta = substitutes[0] - glyphs[0]; 224 for (unsigned int i = 1; i < num_glyphs; i++) 225 if (delta != substitutes[i] - glyphs[i]) { 226 format = 2; 227 break; 228 } 229 } 230 u.format.set (format); 231 switch (u.format) { 232 case 1: return_trace (u.format1.serialize (c, glyphs, num_glyphs, delta)); 233 case 2: return_trace (u.format2.serialize (c, glyphs, substitutes, num_glyphs)); 234 default:return_trace (false); 235 } 236 } 237 238 template <typename context_t> 239 inline typename context_t::return_t dispatch (context_t *c) const 240 { 241 TRACE_DISPATCH (this, u.format); 242 if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); 243 switch (u.format) { 244 case 1: return_trace (c->dispatch (u.format1)); 245 case 2: return_trace (c->dispatch (u.format2)); 246 default:return_trace (c->default_return_value ()); 247 } 248 } 249 250 protected: 251 union { 252 USHORT format; /* Format identifier */ 253 SingleSubstFormat1 format1; 254 SingleSubstFormat2 format2; 255 } u; 256 }; 257 258 259 struct Sequence 260 { 261 inline void closure (hb_closure_context_t *c) const 262 { 263 TRACE_CLOSURE (this); 264 unsigned int count = substitute.len; 265 for (unsigned int i = 0; i < count; i++) 266 c->glyphs->add (substitute[i]); 267 } 268 269 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 270 { 271 TRACE_COLLECT_GLYPHS (this); 272 unsigned int count = substitute.len; 273 for (unsigned int i = 0; i < count; i++) 274 c->output->add (substitute[i]); 275 } 276 277 inline bool apply (hb_apply_context_t *c) const 278 { 279 TRACE_APPLY (this); 280 unsigned int count = substitute.len; 281 282 /* Special-case to make it in-place and not consider this 283 * as a "multiplied" substitution. */ 284 if (unlikely (count == 1)) 285 { 286 c->replace_glyph (substitute.array[0]); 287 return_trace (true); 288 } 289 /* Spec disallows this, but Uniscribe allows it. 290 * https://github.com/behdad/harfbuzz/issues/253 */ 291 else if (unlikely (count == 0)) 292 { 293 c->buffer->delete_glyph (); 294 return_trace (true); 295 } 296 297 unsigned int klass = _hb_glyph_info_is_ligature (&c->buffer->cur()) ? 298 HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH : 0; 299 300 for (unsigned int i = 0; i < count; i++) { 301 _hb_glyph_info_set_lig_props_for_component (&c->buffer->cur(), i); 302 c->output_glyph_for_component (substitute.array[i], klass); 303 } 304 c->buffer->skip_glyph (); 305 306 return_trace (true); 307 } 308 309 inline bool serialize (hb_serialize_context_t *c, 310 Supplier<GlyphID> &glyphs, 311 unsigned int num_glyphs) 312 { 313 TRACE_SERIALIZE (this); 314 if (unlikely (!c->extend_min (*this))) return_trace (false); 315 if (unlikely (!substitute.serialize (c, glyphs, num_glyphs))) return_trace (false); 316 return_trace (true); 317 } 318 319 inline bool sanitize (hb_sanitize_context_t *c) const 320 { 321 TRACE_SANITIZE (this); 322 return_trace (substitute.sanitize (c)); 323 } 324 325 protected: 326 ArrayOf<GlyphID> 327 substitute; /* String of GlyphIDs to substitute */ 328 public: 329 DEFINE_SIZE_ARRAY (2, substitute); 330 }; 331 332 struct MultipleSubstFormat1 333 { 334 inline void closure (hb_closure_context_t *c) const 335 { 336 TRACE_CLOSURE (this); 337 Coverage::Iter iter; 338 unsigned int count = sequence.len; 339 for (iter.init (this+coverage); iter.more (); iter.next ()) 340 { 341 if (unlikely (iter.get_coverage () >= count)) 342 break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ 343 if (c->glyphs->has (iter.get_glyph ())) 344 (this+sequence[iter.get_coverage ()]).closure (c); 345 } 346 } 347 348 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 349 { 350 TRACE_COLLECT_GLYPHS (this); 351 (this+coverage).add_coverage (c->input); 352 unsigned int count = sequence.len; 353 for (unsigned int i = 0; i < count; i++) 354 (this+sequence[i]).collect_glyphs (c); 355 } 356 357 inline const Coverage &get_coverage (void) const 358 { 359 return this+coverage; 360 } 361 362 inline bool would_apply (hb_would_apply_context_t *c) const 363 { 364 TRACE_WOULD_APPLY (this); 365 return_trace (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED); 366 } 367 368 inline bool apply (hb_apply_context_t *c) const 369 { 370 TRACE_APPLY (this); 371 372 unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint); 373 if (likely (index == NOT_COVERED)) return_trace (false); 374 375 return_trace ((this+sequence[index]).apply (c)); 376 } 377 378 inline bool serialize (hb_serialize_context_t *c, 379 Supplier<GlyphID> &glyphs, 380 Supplier<unsigned int> &substitute_len_list, 381 unsigned int num_glyphs, 382 Supplier<GlyphID> &substitute_glyphs_list) 383 { 384 TRACE_SERIALIZE (this); 385 if (unlikely (!c->extend_min (*this))) return_trace (false); 386 if (unlikely (!sequence.serialize (c, num_glyphs))) return_trace (false); 387 for (unsigned int i = 0; i < num_glyphs; i++) 388 if (unlikely (!sequence[i].serialize (c, this).serialize (c, 389 substitute_glyphs_list, 390 substitute_len_list[i]))) return_trace (false); 391 substitute_len_list.advance (num_glyphs); 392 if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return_trace (false); 393 return_trace (true); 394 } 395 396 inline bool sanitize (hb_sanitize_context_t *c) const 397 { 398 TRACE_SANITIZE (this); 399 return_trace (coverage.sanitize (c, this) && sequence.sanitize (c, this)); 400 } 401 402 protected: 403 USHORT format; /* Format identifier--format = 1 */ 404 OffsetTo<Coverage> 405 coverage; /* Offset to Coverage table--from 406 * beginning of Substitution table */ 407 OffsetArrayOf<Sequence> 408 sequence; /* Array of Sequence tables 409 * ordered by Coverage Index */ 410 public: 411 DEFINE_SIZE_ARRAY (6, sequence); 412 }; 413 414 struct MultipleSubst 415 { 416 inline bool serialize (hb_serialize_context_t *c, 417 Supplier<GlyphID> &glyphs, 418 Supplier<unsigned int> &substitute_len_list, 419 unsigned int num_glyphs, 420 Supplier<GlyphID> &substitute_glyphs_list) 421 { 422 TRACE_SERIALIZE (this); 423 if (unlikely (!c->extend_min (u.format))) return_trace (false); 424 unsigned int format = 1; 425 u.format.set (format); 426 switch (u.format) { 427 case 1: return_trace (u.format1.serialize (c, glyphs, substitute_len_list, num_glyphs, substitute_glyphs_list)); 428 default:return_trace (false); 429 } 430 } 431 432 template <typename context_t> 433 inline typename context_t::return_t dispatch (context_t *c) const 434 { 435 TRACE_DISPATCH (this, u.format); 436 if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); 437 switch (u.format) { 438 case 1: return_trace (c->dispatch (u.format1)); 439 default:return_trace (c->default_return_value ()); 440 } 441 } 442 443 protected: 444 union { 445 USHORT format; /* Format identifier */ 446 MultipleSubstFormat1 format1; 447 } u; 448 }; 449 450 451 typedef ArrayOf<GlyphID> AlternateSet; /* Array of alternate GlyphIDs--in 452 * arbitrary order */ 453 454 struct AlternateSubstFormat1 455 { 456 inline void closure (hb_closure_context_t *c) const 457 { 458 TRACE_CLOSURE (this); 459 Coverage::Iter iter; 460 unsigned int count = alternateSet.len; 461 for (iter.init (this+coverage); iter.more (); iter.next ()) 462 { 463 if (unlikely (iter.get_coverage () >= count)) 464 break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ 465 if (c->glyphs->has (iter.get_glyph ())) { 466 const AlternateSet &alt_set = this+alternateSet[iter.get_coverage ()]; 467 unsigned int count = alt_set.len; 468 for (unsigned int i = 0; i < count; i++) 469 c->glyphs->add (alt_set[i]); 470 } 471 } 472 } 473 474 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 475 { 476 TRACE_COLLECT_GLYPHS (this); 477 Coverage::Iter iter; 478 unsigned int count = alternateSet.len; 479 for (iter.init (this+coverage); iter.more (); iter.next ()) 480 { 481 if (unlikely (iter.get_coverage () >= count)) 482 break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ 483 c->input->add (iter.get_glyph ()); 484 const AlternateSet &alt_set = this+alternateSet[iter.get_coverage ()]; 485 unsigned int count = alt_set.len; 486 for (unsigned int i = 0; i < count; i++) 487 c->output->add (alt_set[i]); 488 } 489 } 490 491 inline const Coverage &get_coverage (void) const 492 { 493 return this+coverage; 494 } 495 496 inline bool would_apply (hb_would_apply_context_t *c) const 497 { 498 TRACE_WOULD_APPLY (this); 499 return_trace (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED); 500 } 501 502 inline bool apply (hb_apply_context_t *c) const 503 { 504 TRACE_APPLY (this); 505 hb_codepoint_t glyph_id = c->buffer->cur().codepoint; 506 507 unsigned int index = (this+coverage).get_coverage (glyph_id); 508 if (likely (index == NOT_COVERED)) return_trace (false); 509 510 const AlternateSet &alt_set = this+alternateSet[index]; 511 512 if (unlikely (!alt_set.len)) return_trace (false); 513 514 hb_mask_t glyph_mask = c->buffer->cur().mask; 515 hb_mask_t lookup_mask = c->lookup_mask; 516 517 /* Note: This breaks badly if two features enabled this lookup together. */ 518 unsigned int shift = _hb_ctz (lookup_mask); 519 unsigned int alt_index = ((lookup_mask & glyph_mask) >> shift); 520 521 if (unlikely (alt_index > alt_set.len || alt_index == 0)) return_trace (false); 522 523 glyph_id = alt_set[alt_index - 1]; 524 525 c->replace_glyph (glyph_id); 526 527 return_trace (true); 528 } 529 530 inline bool serialize (hb_serialize_context_t *c, 531 Supplier<GlyphID> &glyphs, 532 Supplier<unsigned int> &alternate_len_list, 533 unsigned int num_glyphs, 534 Supplier<GlyphID> &alternate_glyphs_list) 535 { 536 TRACE_SERIALIZE (this); 537 if (unlikely (!c->extend_min (*this))) return_trace (false); 538 if (unlikely (!alternateSet.serialize (c, num_glyphs))) return_trace (false); 539 for (unsigned int i = 0; i < num_glyphs; i++) 540 if (unlikely (!alternateSet[i].serialize (c, this).serialize (c, 541 alternate_glyphs_list, 542 alternate_len_list[i]))) return_trace (false); 543 alternate_len_list.advance (num_glyphs); 544 if (unlikely (!coverage.serialize (c, this).serialize (c, glyphs, num_glyphs))) return_trace (false); 545 return_trace (true); 546 } 547 548 inline bool sanitize (hb_sanitize_context_t *c) const 549 { 550 TRACE_SANITIZE (this); 551 return_trace (coverage.sanitize (c, this) && alternateSet.sanitize (c, this)); 552 } 553 554 protected: 555 USHORT format; /* Format identifier--format = 1 */ 556 OffsetTo<Coverage> 557 coverage; /* Offset to Coverage table--from 558 * beginning of Substitution table */ 559 OffsetArrayOf<AlternateSet> 560 alternateSet; /* Array of AlternateSet tables 561 * ordered by Coverage Index */ 562 public: 563 DEFINE_SIZE_ARRAY (6, alternateSet); 564 }; 565 566 struct AlternateSubst 567 { 568 inline bool serialize (hb_serialize_context_t *c, 569 Supplier<GlyphID> &glyphs, 570 Supplier<unsigned int> &alternate_len_list, 571 unsigned int num_glyphs, 572 Supplier<GlyphID> &alternate_glyphs_list) 573 { 574 TRACE_SERIALIZE (this); 575 if (unlikely (!c->extend_min (u.format))) return_trace (false); 576 unsigned int format = 1; 577 u.format.set (format); 578 switch (u.format) { 579 case 1: return_trace (u.format1.serialize (c, glyphs, alternate_len_list, num_glyphs, alternate_glyphs_list)); 580 default:return_trace (false); 581 } 582 } 583 584 template <typename context_t> 585 inline typename context_t::return_t dispatch (context_t *c) const 586 { 587 TRACE_DISPATCH (this, u.format); 588 if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); 589 switch (u.format) { 590 case 1: return_trace (c->dispatch (u.format1)); 591 default:return_trace (c->default_return_value ()); 592 } 593 } 594 595 protected: 596 union { 597 USHORT format; /* Format identifier */ 598 AlternateSubstFormat1 format1; 599 } u; 600 }; 601 602 603 struct Ligature 604 { 605 inline void closure (hb_closure_context_t *c) const 606 { 607 TRACE_CLOSURE (this); 608 unsigned int count = component.len; 609 for (unsigned int i = 1; i < count; i++) 610 if (!c->glyphs->has (component[i])) 611 return; 612 c->glyphs->add (ligGlyph); 613 } 614 615 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 616 { 617 TRACE_COLLECT_GLYPHS (this); 618 unsigned int count = component.len; 619 for (unsigned int i = 1; i < count; i++) 620 c->input->add (component[i]); 621 c->output->add (ligGlyph); 622 } 623 624 inline bool would_apply (hb_would_apply_context_t *c) const 625 { 626 TRACE_WOULD_APPLY (this); 627 if (c->len != component.len) 628 return_trace (false); 629 630 for (unsigned int i = 1; i < c->len; i++) 631 if (likely (c->glyphs[i] != component[i])) 632 return_trace (false); 633 634 return_trace (true); 635 } 636 637 inline bool apply (hb_apply_context_t *c) const 638 { 639 TRACE_APPLY (this); 640 unsigned int count = component.len; 641 642 if (unlikely (!count)) return_trace (false); 643 644 /* Special-case to make it in-place and not consider this 645 * as a "ligated" substitution. */ 646 if (unlikely (count == 1)) 647 { 648 c->replace_glyph (ligGlyph); 649 return_trace (true); 650 } 651 652 bool is_mark_ligature = false; 653 unsigned int total_component_count = 0; 654 655 unsigned int match_length = 0; 656 unsigned int match_positions[HB_MAX_CONTEXT_LENGTH]; 657 658 if (likely (!match_input (c, count, 659 &component[1], 660 match_glyph, 661 NULL, 662 &match_length, 663 match_positions, 664 &is_mark_ligature, 665 &total_component_count))) 666 return_trace (false); 667 668 ligate_input (c, 669 count, 670 match_positions, 671 match_length, 672 ligGlyph, 673 is_mark_ligature, 674 total_component_count); 675 676 return_trace (true); 677 } 678 679 inline bool serialize (hb_serialize_context_t *c, 680 GlyphID ligature, 681 Supplier<GlyphID> &components, /* Starting from second */ 682 unsigned int num_components /* Including first component */) 683 { 684 TRACE_SERIALIZE (this); 685 if (unlikely (!c->extend_min (*this))) return_trace (false); 686 ligGlyph = ligature; 687 if (unlikely (!component.serialize (c, components, num_components))) return_trace (false); 688 return_trace (true); 689 } 690 691 public: 692 inline bool sanitize (hb_sanitize_context_t *c) const 693 { 694 TRACE_SANITIZE (this); 695 return_trace (ligGlyph.sanitize (c) && component.sanitize (c)); 696 } 697 698 protected: 699 GlyphID ligGlyph; /* GlyphID of ligature to substitute */ 700 HeadlessArrayOf<GlyphID> 701 component; /* Array of component GlyphIDs--start 702 * with the second component--ordered 703 * in writing direction */ 704 public: 705 DEFINE_SIZE_ARRAY (4, component); 706 }; 707 708 struct LigatureSet 709 { 710 inline void closure (hb_closure_context_t *c) const 711 { 712 TRACE_CLOSURE (this); 713 unsigned int num_ligs = ligature.len; 714 for (unsigned int i = 0; i < num_ligs; i++) 715 (this+ligature[i]).closure (c); 716 } 717 718 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 719 { 720 TRACE_COLLECT_GLYPHS (this); 721 unsigned int num_ligs = ligature.len; 722 for (unsigned int i = 0; i < num_ligs; i++) 723 (this+ligature[i]).collect_glyphs (c); 724 } 725 726 inline bool would_apply (hb_would_apply_context_t *c) const 727 { 728 TRACE_WOULD_APPLY (this); 729 unsigned int num_ligs = ligature.len; 730 for (unsigned int i = 0; i < num_ligs; i++) 731 { 732 const Ligature &lig = this+ligature[i]; 733 if (lig.would_apply (c)) 734 return_trace (true); 735 } 736 return_trace (false); 737 } 738 739 inline bool apply (hb_apply_context_t *c) const 740 { 741 TRACE_APPLY (this); 742 unsigned int num_ligs = ligature.len; 743 for (unsigned int i = 0; i < num_ligs; i++) 744 { 745 const Ligature &lig = this+ligature[i]; 746 if (lig.apply (c)) return_trace (true); 747 } 748 749 return_trace (false); 750 } 751 752 inline bool serialize (hb_serialize_context_t *c, 753 Supplier<GlyphID> &ligatures, 754 Supplier<unsigned int> &component_count_list, 755 unsigned int num_ligatures, 756 Supplier<GlyphID> &component_list /* Starting from second for each ligature */) 757 { 758 TRACE_SERIALIZE (this); 759 if (unlikely (!c->extend_min (*this))) return_trace (false); 760 if (unlikely (!ligature.serialize (c, num_ligatures))) return_trace (false); 761 for (unsigned int i = 0; i < num_ligatures; i++) 762 if (unlikely (!ligature[i].serialize (c, this).serialize (c, 763 ligatures[i], 764 component_list, 765 component_count_list[i]))) return_trace (false); 766 ligatures.advance (num_ligatures); 767 component_count_list.advance (num_ligatures); 768 return_trace (true); 769 } 770 771 inline bool sanitize (hb_sanitize_context_t *c) const 772 { 773 TRACE_SANITIZE (this); 774 return_trace (ligature.sanitize (c, this)); 775 } 776 777 protected: 778 OffsetArrayOf<Ligature> 779 ligature; /* Array LigatureSet tables 780 * ordered by preference */ 781 public: 782 DEFINE_SIZE_ARRAY (2, ligature); 783 }; 784 785 struct LigatureSubstFormat1 786 { 787 inline void closure (hb_closure_context_t *c) const 788 { 789 TRACE_CLOSURE (this); 790 Coverage::Iter iter; 791 unsigned int count = ligatureSet.len; 792 for (iter.init (this+coverage); iter.more (); iter.next ()) 793 { 794 if (unlikely (iter.get_coverage () >= count)) 795 break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ 796 if (c->glyphs->has (iter.get_glyph ())) 797 (this+ligatureSet[iter.get_coverage ()]).closure (c); 798 } 799 } 800 801 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 802 { 803 TRACE_COLLECT_GLYPHS (this); 804 Coverage::Iter iter; 805 unsigned int count = ligatureSet.len; 806 for (iter.init (this+coverage); iter.more (); iter.next ()) 807 { 808 if (unlikely (iter.get_coverage () >= count)) 809 break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ 810 c->input->add (iter.get_glyph ()); 811 (this+ligatureSet[iter.get_coverage ()]).collect_glyphs (c); 812 } 813 } 814 815 inline const Coverage &get_coverage (void) const 816 { 817 return this+coverage; 818 } 819 820 inline bool would_apply (hb_would_apply_context_t *c) const 821 { 822 TRACE_WOULD_APPLY (this); 823 unsigned int index = (this+coverage).get_coverage (c->glyphs[0]); 824 if (likely (index == NOT_COVERED)) return_trace (false); 825 826 const LigatureSet &lig_set = this+ligatureSet[index]; 827 return_trace (lig_set.would_apply (c)); 828 } 829 830 inline bool apply (hb_apply_context_t *c) const 831 { 832 TRACE_APPLY (this); 833 hb_codepoint_t glyph_id = c->buffer->cur().codepoint; 834 835 unsigned int index = (this+coverage).get_coverage (glyph_id); 836 if (likely (index == NOT_COVERED)) return_trace (false); 837 838 const LigatureSet &lig_set = this+ligatureSet[index]; 839 return_trace (lig_set.apply (c)); 840 } 841 842 inline bool serialize (hb_serialize_context_t *c, 843 Supplier<GlyphID> &first_glyphs, 844 Supplier<unsigned int> &ligature_per_first_glyph_count_list, 845 unsigned int num_first_glyphs, 846 Supplier<GlyphID> &ligatures_list, 847 Supplier<unsigned int> &component_count_list, 848 Supplier<GlyphID> &component_list /* Starting from second for each ligature */) 849 { 850 TRACE_SERIALIZE (this); 851 if (unlikely (!c->extend_min (*this))) return_trace (false); 852 if (unlikely (!ligatureSet.serialize (c, num_first_glyphs))) return_trace (false); 853 for (unsigned int i = 0; i < num_first_glyphs; i++) 854 if (unlikely (!ligatureSet[i].serialize (c, this).serialize (c, 855 ligatures_list, 856 component_count_list, 857 ligature_per_first_glyph_count_list[i], 858 component_list))) return_trace (false); 859 ligature_per_first_glyph_count_list.advance (num_first_glyphs); 860 if (unlikely (!coverage.serialize (c, this).serialize (c, first_glyphs, num_first_glyphs))) return_trace (false); 861 return_trace (true); 862 } 863 864 inline bool sanitize (hb_sanitize_context_t *c) const 865 { 866 TRACE_SANITIZE (this); 867 return_trace (coverage.sanitize (c, this) && ligatureSet.sanitize (c, this)); 868 } 869 870 protected: 871 USHORT format; /* Format identifier--format = 1 */ 872 OffsetTo<Coverage> 873 coverage; /* Offset to Coverage table--from 874 * beginning of Substitution table */ 875 OffsetArrayOf<LigatureSet> 876 ligatureSet; /* Array LigatureSet tables 877 * ordered by Coverage Index */ 878 public: 879 DEFINE_SIZE_ARRAY (6, ligatureSet); 880 }; 881 882 struct LigatureSubst 883 { 884 inline bool serialize (hb_serialize_context_t *c, 885 Supplier<GlyphID> &first_glyphs, 886 Supplier<unsigned int> &ligature_per_first_glyph_count_list, 887 unsigned int num_first_glyphs, 888 Supplier<GlyphID> &ligatures_list, 889 Supplier<unsigned int> &component_count_list, 890 Supplier<GlyphID> &component_list /* Starting from second for each ligature */) 891 { 892 TRACE_SERIALIZE (this); 893 if (unlikely (!c->extend_min (u.format))) return_trace (false); 894 unsigned int format = 1; 895 u.format.set (format); 896 switch (u.format) { 897 case 1: return_trace (u.format1.serialize (c, 898 first_glyphs, 899 ligature_per_first_glyph_count_list, 900 num_first_glyphs, 901 ligatures_list, 902 component_count_list, 903 component_list)); 904 default:return_trace (false); 905 } 906 } 907 908 template <typename context_t> 909 inline typename context_t::return_t dispatch (context_t *c) const 910 { 911 TRACE_DISPATCH (this, u.format); 912 if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); 913 switch (u.format) { 914 case 1: return_trace (c->dispatch (u.format1)); 915 default:return_trace (c->default_return_value ()); 916 } 917 } 918 919 protected: 920 union { 921 USHORT format; /* Format identifier */ 922 LigatureSubstFormat1 format1; 923 } u; 924 }; 925 926 927 struct ContextSubst : Context {}; 928 929 struct ChainContextSubst : ChainContext {}; 930 931 struct ExtensionSubst : Extension<ExtensionSubst> 932 { 933 typedef struct SubstLookupSubTable LookupSubTable; 934 935 inline bool is_reverse (void) const; 936 }; 937 938 939 struct ReverseChainSingleSubstFormat1 940 { 941 inline void closure (hb_closure_context_t *c) const 942 { 943 TRACE_CLOSURE (this); 944 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack); 945 946 unsigned int count; 947 948 count = backtrack.len; 949 for (unsigned int i = 0; i < count; i++) 950 if (!(this+backtrack[i]).intersects (c->glyphs)) 951 return; 952 953 count = lookahead.len; 954 for (unsigned int i = 0; i < count; i++) 955 if (!(this+lookahead[i]).intersects (c->glyphs)) 956 return; 957 958 const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead); 959 Coverage::Iter iter; 960 count = substitute.len; 961 for (iter.init (this+coverage); iter.more (); iter.next ()) 962 { 963 if (unlikely (iter.get_coverage () >= count)) 964 break; /* Work around malicious fonts. https://github.com/behdad/harfbuzz/issues/363 */ 965 if (c->glyphs->has (iter.get_glyph ())) 966 c->glyphs->add (substitute[iter.get_coverage ()]); 967 } 968 } 969 970 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 971 { 972 TRACE_COLLECT_GLYPHS (this); 973 974 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack); 975 976 unsigned int count; 977 978 (this+coverage).add_coverage (c->input); 979 980 count = backtrack.len; 981 for (unsigned int i = 0; i < count; i++) 982 (this+backtrack[i]).add_coverage (c->before); 983 984 count = lookahead.len; 985 for (unsigned int i = 0; i < count; i++) 986 (this+lookahead[i]).add_coverage (c->after); 987 988 const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead); 989 count = substitute.len; 990 for (unsigned int i = 0; i < count; i++) 991 c->output->add (substitute[i]); 992 } 993 994 inline const Coverage &get_coverage (void) const 995 { 996 return this+coverage; 997 } 998 999 inline bool would_apply (hb_would_apply_context_t *c) const 1000 { 1001 TRACE_WOULD_APPLY (this); 1002 return_trace (c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED); 1003 } 1004 1005 inline bool apply (hb_apply_context_t *c) const 1006 { 1007 TRACE_APPLY (this); 1008 if (unlikely (c->nesting_level_left != HB_MAX_NESTING_LEVEL)) 1009 return_trace (false); /* No chaining to this type */ 1010 1011 unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint); 1012 if (likely (index == NOT_COVERED)) return_trace (false); 1013 1014 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack); 1015 const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead); 1016 1017 if (match_backtrack (c, 1018 backtrack.len, (USHORT *) backtrack.array, 1019 match_coverage, this) && 1020 match_lookahead (c, 1021 lookahead.len, (USHORT *) lookahead.array, 1022 match_coverage, this, 1023 1)) 1024 { 1025 c->replace_glyph_inplace (substitute[index]); 1026 /* Note: We DON'T decrease buffer->idx. The main loop does it 1027 * for us. This is useful for preventing surprises if someone 1028 * calls us through a Context lookup. */ 1029 return_trace (true); 1030 } 1031 1032 return_trace (false); 1033 } 1034 1035 inline bool sanitize (hb_sanitize_context_t *c) const 1036 { 1037 TRACE_SANITIZE (this); 1038 if (!(coverage.sanitize (c, this) && backtrack.sanitize (c, this))) 1039 return_trace (false); 1040 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack); 1041 if (!lookahead.sanitize (c, this)) 1042 return_trace (false); 1043 const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead); 1044 return_trace (substitute.sanitize (c)); 1045 } 1046 1047 protected: 1048 USHORT format; /* Format identifier--format = 1 */ 1049 OffsetTo<Coverage> 1050 coverage; /* Offset to Coverage table--from 1051 * beginning of table */ 1052 OffsetArrayOf<Coverage> 1053 backtrack; /* Array of coverage tables 1054 * in backtracking sequence, in glyph 1055 * sequence order */ 1056 OffsetArrayOf<Coverage> 1057 lookaheadX; /* Array of coverage tables 1058 * in lookahead sequence, in glyph 1059 * sequence order */ 1060 ArrayOf<GlyphID> 1061 substituteX; /* Array of substitute 1062 * GlyphIDs--ordered by Coverage Index */ 1063 public: 1064 DEFINE_SIZE_MIN (10); 1065 }; 1066 1067 struct ReverseChainSingleSubst 1068 { 1069 template <typename context_t> 1070 inline typename context_t::return_t dispatch (context_t *c) const 1071 { 1072 TRACE_DISPATCH (this, u.format); 1073 if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); 1074 switch (u.format) { 1075 case 1: return_trace (c->dispatch (u.format1)); 1076 default:return_trace (c->default_return_value ()); 1077 } 1078 } 1079 1080 protected: 1081 union { 1082 USHORT format; /* Format identifier */ 1083 ReverseChainSingleSubstFormat1 format1; 1084 } u; 1085 }; 1086 1087 1088 1089 /* 1090 * SubstLookup 1091 */ 1092 1093 struct SubstLookupSubTable 1094 { 1095 friend struct SubstLookup; 1096 1097 enum Type { 1098 Single = 1, 1099 Multiple = 2, 1100 Alternate = 3, 1101 Ligature = 4, 1102 Context = 5, 1103 ChainContext = 6, 1104 Extension = 7, 1105 ReverseChainSingle = 8 1106 }; 1107 1108 template <typename context_t> 1109 inline typename context_t::return_t dispatch (context_t *c, unsigned int lookup_type) const 1110 { 1111 TRACE_DISPATCH (this, lookup_type); 1112 if (unlikely (!c->may_dispatch (this, &u.sub_format))) return_trace (c->no_dispatch_return_value ()); 1113 switch (lookup_type) { 1114 case Single: return_trace (u.single.dispatch (c)); 1115 case Multiple: return_trace (u.multiple.dispatch (c)); 1116 case Alternate: return_trace (u.alternate.dispatch (c)); 1117 case Ligature: return_trace (u.ligature.dispatch (c)); 1118 case Context: return_trace (u.context.dispatch (c)); 1119 case ChainContext: return_trace (u.chainContext.dispatch (c)); 1120 case Extension: return_trace (u.extension.dispatch (c)); 1121 case ReverseChainSingle: return_trace (u.reverseChainContextSingle.dispatch (c)); 1122 default: return_trace (c->default_return_value ()); 1123 } 1124 } 1125 1126 protected: 1127 union { 1128 USHORT sub_format; 1129 SingleSubst single; 1130 MultipleSubst multiple; 1131 AlternateSubst alternate; 1132 LigatureSubst ligature; 1133 ContextSubst context; 1134 ChainContextSubst chainContext; 1135 ExtensionSubst extension; 1136 ReverseChainSingleSubst reverseChainContextSingle; 1137 } u; 1138 public: 1139 DEFINE_SIZE_UNION (2, sub_format); 1140 }; 1141 1142 1143 struct SubstLookup : Lookup 1144 { 1145 inline const SubstLookupSubTable& get_subtable (unsigned int i) const 1146 { return Lookup::get_subtable<SubstLookupSubTable> (i); } 1147 1148 inline static bool lookup_type_is_reverse (unsigned int lookup_type) 1149 { return lookup_type == SubstLookupSubTable::ReverseChainSingle; } 1150 1151 inline bool is_reverse (void) const 1152 { 1153 unsigned int type = get_type (); 1154 if (unlikely (type == SubstLookupSubTable::Extension)) 1155 return CastR<ExtensionSubst> (get_subtable(0)).is_reverse (); 1156 return lookup_type_is_reverse (type); 1157 } 1158 1159 inline bool apply (hb_apply_context_t *c) const 1160 { 1161 TRACE_APPLY (this); 1162 return_trace (dispatch (c)); 1163 } 1164 1165 inline hb_closure_context_t::return_t closure (hb_closure_context_t *c) const 1166 { 1167 TRACE_CLOSURE (this); 1168 c->set_recurse_func (dispatch_recurse_func<hb_closure_context_t>); 1169 return_trace (dispatch (c)); 1170 } 1171 1172 inline hb_collect_glyphs_context_t::return_t collect_glyphs (hb_collect_glyphs_context_t *c) const 1173 { 1174 TRACE_COLLECT_GLYPHS (this); 1175 c->set_recurse_func (dispatch_recurse_func<hb_collect_glyphs_context_t>); 1176 return_trace (dispatch (c)); 1177 } 1178 1179 template <typename set_t> 1180 inline void add_coverage (set_t *glyphs) const 1181 { 1182 hb_add_coverage_context_t<set_t> c (glyphs); 1183 dispatch (&c); 1184 } 1185 1186 inline bool would_apply (hb_would_apply_context_t *c, 1187 const hb_ot_layout_lookup_accelerator_t *accel) const 1188 { 1189 TRACE_WOULD_APPLY (this); 1190 if (unlikely (!c->len)) return_trace (false); 1191 if (!accel->may_have (c->glyphs[0])) return_trace (false); 1192 return_trace (dispatch (c)); 1193 } 1194 1195 static bool apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index); 1196 1197 inline SubstLookupSubTable& serialize_subtable (hb_serialize_context_t *c, 1198 unsigned int i) 1199 { return get_subtables<SubstLookupSubTable> ()[i].serialize (c, this); } 1200 1201 inline bool serialize_single (hb_serialize_context_t *c, 1202 uint32_t lookup_props, 1203 Supplier<GlyphID> &glyphs, 1204 Supplier<GlyphID> &substitutes, 1205 unsigned int num_glyphs) 1206 { 1207 TRACE_SERIALIZE (this); 1208 if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Single, lookup_props, 1))) return_trace (false); 1209 return_trace (serialize_subtable (c, 0).u.single.serialize (c, glyphs, substitutes, num_glyphs)); 1210 } 1211 1212 inline bool serialize_multiple (hb_serialize_context_t *c, 1213 uint32_t lookup_props, 1214 Supplier<GlyphID> &glyphs, 1215 Supplier<unsigned int> &substitute_len_list, 1216 unsigned int num_glyphs, 1217 Supplier<GlyphID> &substitute_glyphs_list) 1218 { 1219 TRACE_SERIALIZE (this); 1220 if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Multiple, lookup_props, 1))) return_trace (false); 1221 return_trace (serialize_subtable (c, 0).u.multiple.serialize (c, 1222 glyphs, 1223 substitute_len_list, 1224 num_glyphs, 1225 substitute_glyphs_list)); 1226 } 1227 1228 inline bool serialize_alternate (hb_serialize_context_t *c, 1229 uint32_t lookup_props, 1230 Supplier<GlyphID> &glyphs, 1231 Supplier<unsigned int> &alternate_len_list, 1232 unsigned int num_glyphs, 1233 Supplier<GlyphID> &alternate_glyphs_list) 1234 { 1235 TRACE_SERIALIZE (this); 1236 if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Alternate, lookup_props, 1))) return_trace (false); 1237 return_trace (serialize_subtable (c, 0).u.alternate.serialize (c, 1238 glyphs, 1239 alternate_len_list, 1240 num_glyphs, 1241 alternate_glyphs_list)); 1242 } 1243 1244 inline bool serialize_ligature (hb_serialize_context_t *c, 1245 uint32_t lookup_props, 1246 Supplier<GlyphID> &first_glyphs, 1247 Supplier<unsigned int> &ligature_per_first_glyph_count_list, 1248 unsigned int num_first_glyphs, 1249 Supplier<GlyphID> &ligatures_list, 1250 Supplier<unsigned int> &component_count_list, 1251 Supplier<GlyphID> &component_list /* Starting from second for each ligature */) 1252 { 1253 TRACE_SERIALIZE (this); 1254 if (unlikely (!Lookup::serialize (c, SubstLookupSubTable::Ligature, lookup_props, 1))) return_trace (false); 1255 return_trace (serialize_subtable (c, 0).u.ligature.serialize (c, 1256 first_glyphs, 1257 ligature_per_first_glyph_count_list, 1258 num_first_glyphs, 1259 ligatures_list, 1260 component_count_list, 1261 component_list)); 1262 } 1263 1264 template <typename context_t> 1265 static inline typename context_t::return_t dispatch_recurse_func (context_t *c, unsigned int lookup_index); 1266 1267 template <typename context_t> 1268 inline typename context_t::return_t dispatch (context_t *c) const 1269 { return Lookup::dispatch<SubstLookupSubTable> (c); } 1270 1271 inline bool sanitize (hb_sanitize_context_t *c) const 1272 { 1273 TRACE_SANITIZE (this); 1274 if (unlikely (!Lookup::sanitize (c))) return_trace (false); 1275 if (unlikely (!dispatch (c))) return_trace (false); 1276 1277 if (unlikely (get_type () == SubstLookupSubTable::Extension)) 1278 { 1279 /* The spec says all subtables of an Extension lookup should 1280 * have the same type. This is specially important if one has 1281 * a reverse type! */ 1282 unsigned int type = get_subtable (0).u.extension.get_type (); 1283 unsigned int count = get_subtable_count (); 1284 for (unsigned int i = 1; i < count; i++) 1285 if (get_subtable (i).u.extension.get_type () != type) 1286 return_trace (false); 1287 } 1288 return_trace (true); 1289 } 1290 }; 1291 1292 typedef OffsetListOf<SubstLookup> SubstLookupList; 1293 1294 /* 1295 * GSUB -- The Glyph Substitution Table 1296 */ 1297 1298 struct GSUB : GSUBGPOS 1299 { 1300 static const hb_tag_t tableTag = HB_OT_TAG_GSUB; 1301 1302 inline const SubstLookup& get_lookup (unsigned int i) const 1303 { return CastR<SubstLookup> (GSUBGPOS::get_lookup (i)); } 1304 1305 static inline void substitute_start (hb_font_t *font, hb_buffer_t *buffer); 1306 1307 inline bool sanitize (hb_sanitize_context_t *c) const 1308 { 1309 TRACE_SANITIZE (this); 1310 if (unlikely (!GSUBGPOS::sanitize (c))) return_trace (false); 1311 const OffsetTo<SubstLookupList> &list = CastR<OffsetTo<SubstLookupList> > (lookupList); 1312 return_trace (list.sanitize (c, this)); 1313 } 1314 }; 1315 1316 1317 void 1318 GSUB::substitute_start (hb_font_t *font, hb_buffer_t *buffer) 1319 { 1320 _hb_buffer_assert_gsubgpos_vars (buffer); 1321 1322 const GDEF &gdef = *hb_ot_layout_from_face (font->face)->gdef; 1323 unsigned int count = buffer->len; 1324 for (unsigned int i = 0; i < count; i++) 1325 { 1326 _hb_glyph_info_set_glyph_props (&buffer->info[i], gdef.get_glyph_props (buffer->info[i].codepoint)); 1327 _hb_glyph_info_clear_lig_props (&buffer->info[i]); 1328 buffer->info[i].syllable() = 0; 1329 } 1330 } 1331 1332 1333 /* Out-of-class implementation for methods recursing */ 1334 1335 /*static*/ inline bool ExtensionSubst::is_reverse (void) const 1336 { 1337 unsigned int type = get_type (); 1338 if (unlikely (type == SubstLookupSubTable::Extension)) 1339 return CastR<ExtensionSubst> (get_subtable<LookupSubTable>()).is_reverse (); 1340 return SubstLookup::lookup_type_is_reverse (type); 1341 } 1342 1343 template <typename context_t> 1344 /*static*/ inline typename context_t::return_t SubstLookup::dispatch_recurse_func (context_t *c, unsigned int lookup_index) 1345 { 1346 const GSUB &gsub = *(hb_ot_layout_from_face (c->face)->gsub); 1347 const SubstLookup &l = gsub.get_lookup (lookup_index); 1348 return l.dispatch (c); 1349 } 1350 1351 /*static*/ inline bool SubstLookup::apply_recurse_func (hb_apply_context_t *c, unsigned int lookup_index) 1352 { 1353 const GSUB &gsub = *(hb_ot_layout_from_face (c->face)->gsub); 1354 const SubstLookup &l = gsub.get_lookup (lookup_index); 1355 unsigned int saved_lookup_props = c->lookup_props; 1356 unsigned int saved_lookup_index = c->lookup_index; 1357 c->set_lookup_index (lookup_index); 1358 c->set_lookup_props (l.get_props ()); 1359 bool ret = l.dispatch (c); 1360 c->set_lookup_index (saved_lookup_index); 1361 c->set_lookup_props (saved_lookup_props); 1362 return ret; 1363 } 1364 1365 1366 } /* namespace OT */ 1367 1368 1369 #endif /* HB_OT_LAYOUT_GSUB_TABLE_HH */ 1370
