1 /* 2 * Copyright 2007,2008,2009,2010 Red Hat, Inc. 3 * Copyright 2010,2012 Google, Inc. 4 * 5 * This is part of HarfBuzz, a text shaping library. 6 * 7 * Permission is hereby granted, without written agreement and without 8 * license or royalty fees, to use, copy, modify, and distribute this 9 * software and its documentation for any purpose, provided that the 10 * above copyright notice and the following two paragraphs appear in 11 * all copies of this software. 12 * 13 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 14 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 15 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 16 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 17 * DAMAGE. 18 * 19 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 20 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 21 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 22 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 23 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 24 * 25 * Red Hat Author(s): Behdad Esfahbod 26 * Google Author(s): Behdad Esfahbod 27 */ 28 29 #ifndef HB_OT_LAYOUT_GSUBGPOS_PRIVATE_HH 30 #define HB_OT_LAYOUT_GSUBGPOS_PRIVATE_HH 31 32 #include "hb-buffer-private.hh" 33 #include "hb-ot-layout-gdef-table.hh" 34 #include "hb-set-private.hh" 35 36 37 namespace OT { 38 39 40 #ifndef HB_DEBUG_CLOSURE 41 #define HB_DEBUG_CLOSURE (HB_DEBUG+0) 42 #endif 43 44 #define TRACE_CLOSURE(this) \ 45 hb_auto_trace_t<HB_DEBUG_CLOSURE, hb_void_t> trace \ 46 (&c->debug_depth, c->get_name (), this, HB_FUNC, \ 47 ""); 48 49 struct hb_closure_context_t : 50 hb_dispatch_context_t<hb_closure_context_t, hb_void_t, HB_DEBUG_CLOSURE> 51 { 52 inline const char *get_name (void) { return "CLOSURE"; } 53 typedef return_t (*recurse_func_t) (hb_closure_context_t *c, unsigned int lookup_index); 54 template <typename T> 55 inline return_t dispatch (const T &obj) { obj.closure (this); return HB_VOID; } 56 static return_t default_return_value (void) { return HB_VOID; } 57 bool stop_sublookup_iteration (return_t r HB_UNUSED) const { return false; } 58 return_t recurse (unsigned int lookup_index) 59 { 60 if (unlikely (nesting_level_left == 0 || !recurse_func)) 61 return default_return_value (); 62 63 nesting_level_left--; 64 recurse_func (this, lookup_index); 65 nesting_level_left++; 66 return HB_VOID; 67 } 68 69 hb_face_t *face; 70 hb_set_t *glyphs; 71 recurse_func_t recurse_func; 72 unsigned int nesting_level_left; 73 unsigned int debug_depth; 74 75 hb_closure_context_t (hb_face_t *face_, 76 hb_set_t *glyphs_, 77 unsigned int nesting_level_left_ = HB_MAX_NESTING_LEVEL) : 78 face (face_), 79 glyphs (glyphs_), 80 recurse_func (NULL), 81 nesting_level_left (nesting_level_left_), 82 debug_depth (0) {} 83 84 void set_recurse_func (recurse_func_t func) { recurse_func = func; } 85 }; 86 87 88 89 #ifndef HB_DEBUG_WOULD_APPLY 90 #define HB_DEBUG_WOULD_APPLY (HB_DEBUG+0) 91 #endif 92 93 #define TRACE_WOULD_APPLY(this) \ 94 hb_auto_trace_t<HB_DEBUG_WOULD_APPLY, bool> trace \ 95 (&c->debug_depth, c->get_name (), this, HB_FUNC, \ 96 "%d glyphs", c->len); 97 98 struct hb_would_apply_context_t : 99 hb_dispatch_context_t<hb_would_apply_context_t, bool, HB_DEBUG_WOULD_APPLY> 100 { 101 inline const char *get_name (void) { return "WOULD_APPLY"; } 102 template <typename T> 103 inline return_t dispatch (const T &obj) { return obj.would_apply (this); } 104 static return_t default_return_value (void) { return false; } 105 bool stop_sublookup_iteration (return_t r) const { return r; } 106 107 hb_face_t *face; 108 const hb_codepoint_t *glyphs; 109 unsigned int len; 110 bool zero_context; 111 unsigned int debug_depth; 112 113 hb_would_apply_context_t (hb_face_t *face_, 114 const hb_codepoint_t *glyphs_, 115 unsigned int len_, 116 bool zero_context_) : 117 face (face_), 118 glyphs (glyphs_), 119 len (len_), 120 zero_context (zero_context_), 121 debug_depth (0) {} 122 }; 123 124 125 126 #ifndef HB_DEBUG_COLLECT_GLYPHS 127 #define HB_DEBUG_COLLECT_GLYPHS (HB_DEBUG+0) 128 #endif 129 130 #define TRACE_COLLECT_GLYPHS(this) \ 131 hb_auto_trace_t<HB_DEBUG_COLLECT_GLYPHS, hb_void_t> trace \ 132 (&c->debug_depth, c->get_name (), this, HB_FUNC, \ 133 ""); 134 135 struct hb_collect_glyphs_context_t : 136 hb_dispatch_context_t<hb_collect_glyphs_context_t, hb_void_t, HB_DEBUG_COLLECT_GLYPHS> 137 { 138 inline const char *get_name (void) { return "COLLECT_GLYPHS"; } 139 typedef return_t (*recurse_func_t) (hb_collect_glyphs_context_t *c, unsigned int lookup_index); 140 template <typename T> 141 inline return_t dispatch (const T &obj) { obj.collect_glyphs (this); return HB_VOID; } 142 static return_t default_return_value (void) { return HB_VOID; } 143 bool stop_sublookup_iteration (return_t r HB_UNUSED) const { return false; } 144 return_t recurse (unsigned int lookup_index) 145 { 146 if (unlikely (nesting_level_left == 0 || !recurse_func)) 147 return default_return_value (); 148 149 /* Note that GPOS sets recurse_func to NULL already, so it doesn't get 150 * past the previous check. For GSUB, we only want to collect the output 151 * glyphs in the recursion. If output is not requested, we can go home now. 152 * 153 * Note further, that the above is not exactly correct. A recursed lookup 154 * is allowed to match input that is not matched in the context, but that's 155 * not how most fonts are built. It's possible to relax that and recurse 156 * with all sets here if it proves to be an issue. 157 */ 158 159 if (output == hb_set_get_empty ()) 160 return HB_VOID; 161 162 /* Return if new lookup was recursed to before. */ 163 if (recursed_lookups.has (lookup_index)) 164 return HB_VOID; 165 166 hb_set_t *old_before = before; 167 hb_set_t *old_input = input; 168 hb_set_t *old_after = after; 169 before = input = after = hb_set_get_empty (); 170 171 nesting_level_left--; 172 recurse_func (this, lookup_index); 173 nesting_level_left++; 174 175 before = old_before; 176 input = old_input; 177 after = old_after; 178 179 recursed_lookups.add (lookup_index); 180 181 return HB_VOID; 182 } 183 184 hb_face_t *face; 185 hb_set_t *before; 186 hb_set_t *input; 187 hb_set_t *after; 188 hb_set_t *output; 189 recurse_func_t recurse_func; 190 hb_set_t recursed_lookups; 191 unsigned int nesting_level_left; 192 unsigned int debug_depth; 193 194 hb_collect_glyphs_context_t (hb_face_t *face_, 195 hb_set_t *glyphs_before, /* OUT. May be NULL */ 196 hb_set_t *glyphs_input, /* OUT. May be NULL */ 197 hb_set_t *glyphs_after, /* OUT. May be NULL */ 198 hb_set_t *glyphs_output, /* OUT. May be NULL */ 199 unsigned int nesting_level_left_ = HB_MAX_NESTING_LEVEL) : 200 face (face_), 201 before (glyphs_before ? glyphs_before : hb_set_get_empty ()), 202 input (glyphs_input ? glyphs_input : hb_set_get_empty ()), 203 after (glyphs_after ? glyphs_after : hb_set_get_empty ()), 204 output (glyphs_output ? glyphs_output : hb_set_get_empty ()), 205 recurse_func (NULL), 206 recursed_lookups (), 207 nesting_level_left (nesting_level_left_), 208 debug_depth (0) 209 { 210 recursed_lookups.init (); 211 } 212 ~hb_collect_glyphs_context_t (void) 213 { 214 recursed_lookups.fini (); 215 } 216 217 void set_recurse_func (recurse_func_t func) { recurse_func = func; } 218 }; 219 220 221 222 #ifndef HB_DEBUG_GET_COVERAGE 223 #define HB_DEBUG_GET_COVERAGE (HB_DEBUG+0) 224 #endif 225 226 /* XXX Can we remove this? */ 227 228 template <typename set_t> 229 struct hb_add_coverage_context_t : 230 hb_dispatch_context_t<hb_add_coverage_context_t<set_t>, const Coverage &, HB_DEBUG_GET_COVERAGE> 231 { 232 inline const char *get_name (void) { return "GET_COVERAGE"; } 233 typedef const Coverage &return_t; 234 template <typename T> 235 inline return_t dispatch (const T &obj) { return obj.get_coverage (); } 236 static return_t default_return_value (void) { return Null(Coverage); } 237 bool stop_sublookup_iteration (return_t r) const 238 { 239 r.add_coverage (set); 240 return false; 241 } 242 243 hb_add_coverage_context_t (set_t *set_) : 244 set (set_), 245 debug_depth (0) {} 246 247 set_t *set; 248 unsigned int debug_depth; 249 }; 250 251 252 253 #ifndef HB_DEBUG_APPLY 254 #define HB_DEBUG_APPLY (HB_DEBUG+0) 255 #endif 256 257 #define TRACE_APPLY(this) \ 258 hb_auto_trace_t<HB_DEBUG_APPLY, bool> trace \ 259 (&c->debug_depth, c->get_name (), this, HB_FUNC, \ 260 "idx %d gid %u lookup %d", \ 261 c->buffer->idx, c->buffer->cur().codepoint, (int) c->lookup_index); 262 263 struct hb_apply_context_t : 264 hb_dispatch_context_t<hb_apply_context_t, bool, HB_DEBUG_APPLY> 265 { 266 struct matcher_t 267 { 268 inline matcher_t (void) : 269 lookup_props (0), 270 ignore_zwnj (false), 271 ignore_zwj (false), 272 mask (-1), 273 #define arg1(arg) (arg) /* Remove the macro to see why it's needed! */ 274 syllable arg1(0), 275 #undef arg1 276 match_func (NULL), 277 match_data (NULL) {}; 278 279 typedef bool (*match_func_t) (hb_codepoint_t glyph_id, const USHORT &value, const void *data); 280 281 inline void set_ignore_zwnj (bool ignore_zwnj_) { ignore_zwnj = ignore_zwnj_; } 282 inline void set_ignore_zwj (bool ignore_zwj_) { ignore_zwj = ignore_zwj_; } 283 inline void set_lookup_props (unsigned int lookup_props_) { lookup_props = lookup_props_; } 284 inline void set_mask (hb_mask_t mask_) { mask = mask_; } 285 inline void set_syllable (uint8_t syllable_) { syllable = syllable_; } 286 inline void set_match_func (match_func_t match_func_, 287 const void *match_data_) 288 { match_func = match_func_; match_data = match_data_; } 289 290 enum may_match_t { 291 MATCH_NO, 292 MATCH_YES, 293 MATCH_MAYBE 294 }; 295 296 inline may_match_t may_match (const hb_glyph_info_t &info, 297 const USHORT *glyph_data) const 298 { 299 if (!(info.mask & mask) || 300 (syllable && syllable != info.syllable ())) 301 return MATCH_NO; 302 303 if (match_func) 304 return match_func (info.codepoint, *glyph_data, match_data) ? MATCH_YES : MATCH_NO; 305 306 return MATCH_MAYBE; 307 } 308 309 enum may_skip_t { 310 SKIP_NO, 311 SKIP_YES, 312 SKIP_MAYBE 313 }; 314 315 inline may_skip_t 316 may_skip (const hb_apply_context_t *c, 317 const hb_glyph_info_t &info) const 318 { 319 if (!c->check_glyph_property (&info, lookup_props)) 320 return SKIP_YES; 321 322 if (unlikely (_hb_glyph_info_is_default_ignorable_and_not_fvs (&info) && 323 (ignore_zwnj || !_hb_glyph_info_is_zwnj (&info)) && 324 (ignore_zwj || !_hb_glyph_info_is_zwj (&info)))) 325 return SKIP_MAYBE; 326 327 return SKIP_NO; 328 } 329 330 protected: 331 unsigned int lookup_props; 332 bool ignore_zwnj; 333 bool ignore_zwj; 334 hb_mask_t mask; 335 uint8_t syllable; 336 match_func_t match_func; 337 const void *match_data; 338 }; 339 340 struct skipping_iterator_t 341 { 342 inline void init (hb_apply_context_t *c_, bool context_match = false) 343 { 344 c = c_; 345 match_glyph_data = NULL, 346 matcher.set_match_func (NULL, NULL); 347 matcher.set_lookup_props (c->lookup_props); 348 /* Ignore ZWNJ if we are matching GSUB context, or matching GPOS. */ 349 matcher.set_ignore_zwnj (context_match || c->table_index == 1); 350 /* Ignore ZWJ if we are matching GSUB context, or matching GPOS, or if asked to. */ 351 matcher.set_ignore_zwj (context_match || c->table_index == 1 || c->auto_zwj); 352 matcher.set_mask (context_match ? -1 : c->lookup_mask); 353 } 354 inline void set_lookup_props (unsigned int lookup_props) 355 { 356 matcher.set_lookup_props (lookup_props); 357 } 358 inline void set_match_func (matcher_t::match_func_t match_func_, 359 const void *match_data_, 360 const USHORT glyph_data[]) 361 { 362 matcher.set_match_func (match_func_, match_data_); 363 match_glyph_data = glyph_data; 364 } 365 366 inline void reset (unsigned int start_index_, 367 unsigned int num_items_) 368 { 369 idx = start_index_; 370 num_items = num_items_; 371 end = c->buffer->len; 372 matcher.set_syllable (start_index_ == c->buffer->idx ? c->buffer->cur().syllable () : 0); 373 } 374 375 inline void reject (void) { num_items++; match_glyph_data--; } 376 377 inline bool next (void) 378 { 379 assert (num_items > 0); 380 while (idx + num_items < end) 381 { 382 idx++; 383 const hb_glyph_info_t &info = c->buffer->info[idx]; 384 385 matcher_t::may_skip_t skip = matcher.may_skip (c, info); 386 if (unlikely (skip == matcher_t::SKIP_YES)) 387 continue; 388 389 matcher_t::may_match_t match = matcher.may_match (info, match_glyph_data); 390 if (match == matcher_t::MATCH_YES || 391 (match == matcher_t::MATCH_MAYBE && 392 skip == matcher_t::SKIP_NO)) 393 { 394 num_items--; 395 match_glyph_data++; 396 return true; 397 } 398 399 if (skip == matcher_t::SKIP_NO) 400 return false; 401 } 402 return false; 403 } 404 inline bool prev (void) 405 { 406 assert (num_items > 0); 407 while (idx >= num_items) 408 { 409 idx--; 410 const hb_glyph_info_t &info = c->buffer->out_info[idx]; 411 412 matcher_t::may_skip_t skip = matcher.may_skip (c, info); 413 if (unlikely (skip == matcher_t::SKIP_YES)) 414 continue; 415 416 matcher_t::may_match_t match = matcher.may_match (info, match_glyph_data); 417 if (match == matcher_t::MATCH_YES || 418 (match == matcher_t::MATCH_MAYBE && 419 skip == matcher_t::SKIP_NO)) 420 { 421 num_items--; 422 match_glyph_data++; 423 return true; 424 } 425 426 if (skip == matcher_t::SKIP_NO) 427 return false; 428 } 429 return false; 430 } 431 432 unsigned int idx; 433 protected: 434 hb_apply_context_t *c; 435 matcher_t matcher; 436 const USHORT *match_glyph_data; 437 438 unsigned int num_items; 439 unsigned int end; 440 }; 441 442 443 inline const char *get_name (void) { return "APPLY"; } 444 typedef return_t (*recurse_func_t) (hb_apply_context_t *c, unsigned int lookup_index); 445 template <typename T> 446 inline return_t dispatch (const T &obj) { return obj.apply (this); } 447 static return_t default_return_value (void) { return false; } 448 bool stop_sublookup_iteration (return_t r) const { return r; } 449 return_t recurse (unsigned int lookup_index) 450 { 451 if (unlikely (nesting_level_left == 0 || !recurse_func)) 452 return default_return_value (); 453 454 nesting_level_left--; 455 bool ret = recurse_func (this, lookup_index); 456 nesting_level_left++; 457 return ret; 458 } 459 460 unsigned int table_index; /* GSUB/GPOS */ 461 hb_font_t *font; 462 hb_face_t *face; 463 hb_buffer_t *buffer; 464 hb_direction_t direction; 465 hb_mask_t lookup_mask; 466 bool auto_zwj; 467 recurse_func_t recurse_func; 468 unsigned int nesting_level_left; 469 unsigned int lookup_props; 470 const GDEF &gdef; 471 bool has_glyph_classes; 472 const VariationStore &var_store; 473 skipping_iterator_t iter_input, iter_context; 474 unsigned int lookup_index; 475 unsigned int debug_depth; 476 477 478 hb_apply_context_t (unsigned int table_index_, 479 hb_font_t *font_, 480 hb_buffer_t *buffer_) : 481 table_index (table_index_), 482 font (font_), face (font->face), buffer (buffer_), 483 direction (buffer_->props.direction), 484 lookup_mask (1), 485 auto_zwj (true), 486 recurse_func (NULL), 487 nesting_level_left (HB_MAX_NESTING_LEVEL), 488 lookup_props (0), 489 gdef (*hb_ot_layout_from_face (face)->gdef), 490 has_glyph_classes (gdef.has_glyph_classes ()), 491 var_store (gdef.get_var_store ()), 492 iter_input (), 493 iter_context (), 494 lookup_index ((unsigned int) -1), 495 debug_depth (0) {} 496 497 inline void set_lookup_mask (hb_mask_t mask) { lookup_mask = mask; } 498 inline void set_auto_zwj (bool auto_zwj_) { auto_zwj = auto_zwj_; } 499 inline void set_recurse_func (recurse_func_t func) { recurse_func = func; } 500 inline void set_lookup_index (unsigned int lookup_index_) { lookup_index = lookup_index_; } 501 inline void set_lookup_props (unsigned int lookup_props_) 502 { 503 lookup_props = lookup_props_; 504 iter_input.init (this, false); 505 iter_context.init (this, true); 506 } 507 508 inline bool 509 match_properties_mark (hb_codepoint_t glyph, 510 unsigned int glyph_props, 511 unsigned int match_props) const 512 { 513 /* If using mark filtering sets, the high short of 514 * match_props has the set index. 515 */ 516 if (match_props & LookupFlag::UseMarkFilteringSet) 517 return gdef.mark_set_covers (match_props >> 16, glyph); 518 519 /* The second byte of match_props has the meaning 520 * "ignore marks of attachment type different than 521 * the attachment type specified." 522 */ 523 if (match_props & LookupFlag::MarkAttachmentType) 524 return (match_props & LookupFlag::MarkAttachmentType) == (glyph_props & LookupFlag::MarkAttachmentType); 525 526 return true; 527 } 528 529 inline bool 530 check_glyph_property (const hb_glyph_info_t *info, 531 unsigned int match_props) const 532 { 533 hb_codepoint_t glyph = info->codepoint; 534 unsigned int glyph_props = _hb_glyph_info_get_glyph_props (info); 535 536 /* Not covered, if, for example, glyph class is ligature and 537 * match_props includes LookupFlags::IgnoreLigatures 538 */ 539 if (glyph_props & match_props & LookupFlag::IgnoreFlags) 540 return false; 541 542 if (unlikely (glyph_props & HB_OT_LAYOUT_GLYPH_PROPS_MARK)) 543 return match_properties_mark (glyph, glyph_props, match_props); 544 545 return true; 546 } 547 548 inline void _set_glyph_props (hb_codepoint_t glyph_index, 549 unsigned int class_guess = 0, 550 bool ligature = false, 551 bool component = false) const 552 { 553 unsigned int add_in = _hb_glyph_info_get_glyph_props (&buffer->cur()) & 554 HB_OT_LAYOUT_GLYPH_PROPS_PRESERVE; 555 add_in |= HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED; 556 if (ligature) 557 { 558 add_in |= HB_OT_LAYOUT_GLYPH_PROPS_LIGATED; 559 /* In the only place that the MULTIPLIED bit is used, Uniscribe 560 * seems to only care about the "last" transformation between 561 * Ligature and Multiple substitions. Ie. if you ligate, expand, 562 * and ligate again, it forgives the multiplication and acts as 563 * if only ligation happened. As such, clear MULTIPLIED bit. 564 */ 565 add_in &= ~HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED; 566 } 567 if (component) 568 add_in |= HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED; 569 if (likely (has_glyph_classes)) 570 _hb_glyph_info_set_glyph_props (&buffer->cur(), add_in | gdef.get_glyph_props (glyph_index)); 571 else if (class_guess) 572 _hb_glyph_info_set_glyph_props (&buffer->cur(), add_in | class_guess); 573 } 574 575 inline void replace_glyph (hb_codepoint_t glyph_index) const 576 { 577 _set_glyph_props (glyph_index); 578 buffer->replace_glyph (glyph_index); 579 } 580 inline void replace_glyph_inplace (hb_codepoint_t glyph_index) const 581 { 582 _set_glyph_props (glyph_index); 583 buffer->cur().codepoint = glyph_index; 584 } 585 inline void replace_glyph_with_ligature (hb_codepoint_t glyph_index, 586 unsigned int class_guess) const 587 { 588 _set_glyph_props (glyph_index, class_guess, true); 589 buffer->replace_glyph (glyph_index); 590 } 591 inline void output_glyph_for_component (hb_codepoint_t glyph_index, 592 unsigned int class_guess) const 593 { 594 _set_glyph_props (glyph_index, class_guess, false, true); 595 buffer->output_glyph (glyph_index); 596 } 597 }; 598 599 600 601 typedef bool (*intersects_func_t) (hb_set_t *glyphs, const USHORT &value, const void *data); 602 typedef void (*collect_glyphs_func_t) (hb_set_t *glyphs, const USHORT &value, const void *data); 603 typedef bool (*match_func_t) (hb_codepoint_t glyph_id, const USHORT &value, const void *data); 604 605 struct ContextClosureFuncs 606 { 607 intersects_func_t intersects; 608 }; 609 struct ContextCollectGlyphsFuncs 610 { 611 collect_glyphs_func_t collect; 612 }; 613 struct ContextApplyFuncs 614 { 615 match_func_t match; 616 }; 617 618 619 static inline bool intersects_glyph (hb_set_t *glyphs, const USHORT &value, const void *data HB_UNUSED) 620 { 621 return glyphs->has (value); 622 } 623 static inline bool intersects_class (hb_set_t *glyphs, const USHORT &value, const void *data) 624 { 625 const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data); 626 return class_def.intersects_class (glyphs, value); 627 } 628 static inline bool intersects_coverage (hb_set_t *glyphs, const USHORT &value, const void *data) 629 { 630 const OffsetTo<Coverage> &coverage = (const OffsetTo<Coverage>&)value; 631 return (data+coverage).intersects (glyphs); 632 } 633 634 static inline bool intersects_array (hb_closure_context_t *c, 635 unsigned int count, 636 const USHORT values[], 637 intersects_func_t intersects_func, 638 const void *intersects_data) 639 { 640 for (unsigned int i = 0; i < count; i++) 641 if (likely (!intersects_func (c->glyphs, values[i], intersects_data))) 642 return false; 643 return true; 644 } 645 646 647 static inline void collect_glyph (hb_set_t *glyphs, const USHORT &value, const void *data HB_UNUSED) 648 { 649 glyphs->add (value); 650 } 651 static inline void collect_class (hb_set_t *glyphs, const USHORT &value, const void *data) 652 { 653 const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data); 654 class_def.add_class (glyphs, value); 655 } 656 static inline void collect_coverage (hb_set_t *glyphs, const USHORT &value, const void *data) 657 { 658 const OffsetTo<Coverage> &coverage = (const OffsetTo<Coverage>&)value; 659 (data+coverage).add_coverage (glyphs); 660 } 661 static inline void collect_array (hb_collect_glyphs_context_t *c HB_UNUSED, 662 hb_set_t *glyphs, 663 unsigned int count, 664 const USHORT values[], 665 collect_glyphs_func_t collect_func, 666 const void *collect_data) 667 { 668 for (unsigned int i = 0; i < count; i++) 669 collect_func (glyphs, values[i], collect_data); 670 } 671 672 673 static inline bool match_glyph (hb_codepoint_t glyph_id, const USHORT &value, const void *data HB_UNUSED) 674 { 675 return glyph_id == value; 676 } 677 static inline bool match_class (hb_codepoint_t glyph_id, const USHORT &value, const void *data) 678 { 679 const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data); 680 return class_def.get_class (glyph_id) == value; 681 } 682 static inline bool match_coverage (hb_codepoint_t glyph_id, const USHORT &value, const void *data) 683 { 684 const OffsetTo<Coverage> &coverage = (const OffsetTo<Coverage>&)value; 685 return (data+coverage).get_coverage (glyph_id) != NOT_COVERED; 686 } 687 688 static inline bool would_match_input (hb_would_apply_context_t *c, 689 unsigned int count, /* Including the first glyph (not matched) */ 690 const USHORT input[], /* Array of input values--start with second glyph */ 691 match_func_t match_func, 692 const void *match_data) 693 { 694 if (count != c->len) 695 return false; 696 697 for (unsigned int i = 1; i < count; i++) 698 if (likely (!match_func (c->glyphs[i], input[i - 1], match_data))) 699 return false; 700 701 return true; 702 } 703 static inline bool match_input (hb_apply_context_t *c, 704 unsigned int count, /* Including the first glyph (not matched) */ 705 const USHORT input[], /* Array of input values--start with second glyph */ 706 match_func_t match_func, 707 const void *match_data, 708 unsigned int *end_offset, 709 unsigned int match_positions[HB_MAX_CONTEXT_LENGTH], 710 bool *p_is_mark_ligature = NULL, 711 unsigned int *p_total_component_count = NULL) 712 { 713 TRACE_APPLY (NULL); 714 715 if (unlikely (count > HB_MAX_CONTEXT_LENGTH)) return_trace (false); 716 717 hb_buffer_t *buffer = c->buffer; 718 719 hb_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input; 720 skippy_iter.reset (buffer->idx, count - 1); 721 skippy_iter.set_match_func (match_func, match_data, input); 722 723 /* 724 * This is perhaps the trickiest part of OpenType... Remarks: 725 * 726 * - If all components of the ligature were marks, we call this a mark ligature. 727 * 728 * - If there is no GDEF, and the ligature is NOT a mark ligature, we categorize 729 * it as a ligature glyph. 730 * 731 * - Ligatures cannot be formed across glyphs attached to different components 732 * of previous ligatures. Eg. the sequence is LAM,SHADDA,LAM,FATHA,HEH, and 733 * LAM,LAM,HEH form a ligature, leaving SHADDA,FATHA next to eachother. 734 * However, it would be wrong to ligate that SHADDA,FATHA sequence.o 735 * There is an exception to this: If a ligature tries ligating with marks that 736 * belong to it itself, go ahead, assuming that the font designer knows what 737 * they are doing (otherwise it can break Indic stuff when a matra wants to 738 * ligate with a conjunct...) 739 */ 740 741 bool is_mark_ligature = _hb_glyph_info_is_mark (&buffer->cur()); 742 743 unsigned int total_component_count = 0; 744 total_component_count += _hb_glyph_info_get_lig_num_comps (&buffer->cur()); 745 746 unsigned int first_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur()); 747 unsigned int first_lig_comp = _hb_glyph_info_get_lig_comp (&buffer->cur()); 748 749 match_positions[0] = buffer->idx; 750 for (unsigned int i = 1; i < count; i++) 751 { 752 if (!skippy_iter.next ()) return_trace (false); 753 754 match_positions[i] = skippy_iter.idx; 755 756 unsigned int this_lig_id = _hb_glyph_info_get_lig_id (&buffer->info[skippy_iter.idx]); 757 unsigned int this_lig_comp = _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx]); 758 759 if (first_lig_id && first_lig_comp) { 760 /* If first component was attached to a previous ligature component, 761 * all subsequent components should be attached to the same ligature 762 * component, otherwise we shouldn't ligate them. */ 763 if (first_lig_id != this_lig_id || first_lig_comp != this_lig_comp) 764 return_trace (false); 765 } else { 766 /* If first component was NOT attached to a previous ligature component, 767 * all subsequent components should also NOT be attached to any ligature 768 * component, unless they are attached to the first component itself! */ 769 if (this_lig_id && this_lig_comp && (this_lig_id != first_lig_id)) 770 return_trace (false); 771 } 772 773 is_mark_ligature = is_mark_ligature && _hb_glyph_info_is_mark (&buffer->info[skippy_iter.idx]); 774 total_component_count += _hb_glyph_info_get_lig_num_comps (&buffer->info[skippy_iter.idx]); 775 } 776 777 *end_offset = skippy_iter.idx - buffer->idx + 1; 778 779 if (p_is_mark_ligature) 780 *p_is_mark_ligature = is_mark_ligature; 781 782 if (p_total_component_count) 783 *p_total_component_count = total_component_count; 784 785 return_trace (true); 786 } 787 static inline bool ligate_input (hb_apply_context_t *c, 788 unsigned int count, /* Including the first glyph */ 789 unsigned int match_positions[HB_MAX_CONTEXT_LENGTH], /* Including the first glyph */ 790 unsigned int match_length, 791 hb_codepoint_t lig_glyph, 792 bool is_mark_ligature, 793 unsigned int total_component_count) 794 { 795 TRACE_APPLY (NULL); 796 797 hb_buffer_t *buffer = c->buffer; 798 799 buffer->merge_clusters (buffer->idx, buffer->idx + match_length); 800 801 /* 802 * - If it *is* a mark ligature, we don't allocate a new ligature id, and leave 803 * the ligature to keep its old ligature id. This will allow it to attach to 804 * a base ligature in GPOS. Eg. if the sequence is: LAM,LAM,SHADDA,FATHA,HEH, 805 * and LAM,LAM,HEH for a ligature, they will leave SHADDA and FATHA wit a 806 * ligature id and component value of 2. Then if SHADDA,FATHA form a ligature 807 * later, we don't want them to lose their ligature id/component, otherwise 808 * GPOS will fail to correctly position the mark ligature on top of the 809 * LAM,LAM,HEH ligature. See: 810 * https://bugzilla.gnome.org/show_bug.cgi?id=676343 811 * 812 * - If a ligature is formed of components that some of which are also ligatures 813 * themselves, and those ligature components had marks attached to *their* 814 * components, we have to attach the marks to the new ligature component 815 * positions! Now *that*'s tricky! And these marks may be following the 816 * last component of the whole sequence, so we should loop forward looking 817 * for them and update them. 818 * 819 * Eg. the sequence is LAM,LAM,SHADDA,FATHA,HEH, and the font first forms a 820 * 'calt' ligature of LAM,HEH, leaving the SHADDA and FATHA with a ligature 821 * id and component == 1. Now, during 'liga', the LAM and the LAM-HEH ligature 822 * form a LAM-LAM-HEH ligature. We need to reassign the SHADDA and FATHA to 823 * the new ligature with a component value of 2. 824 * 825 * This in fact happened to a font... See: 826 * https://bugzilla.gnome.org/show_bug.cgi?id=437633 827 */ 828 829 unsigned int klass = is_mark_ligature ? 0 : HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE; 830 unsigned int lig_id = is_mark_ligature ? 0 : _hb_allocate_lig_id (buffer); 831 unsigned int last_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur()); 832 unsigned int last_num_components = _hb_glyph_info_get_lig_num_comps (&buffer->cur()); 833 unsigned int components_so_far = last_num_components; 834 835 if (!is_mark_ligature) 836 { 837 _hb_glyph_info_set_lig_props_for_ligature (&buffer->cur(), lig_id, total_component_count); 838 if (_hb_glyph_info_get_general_category (&buffer->cur()) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) 839 { 840 _hb_glyph_info_set_general_category (&buffer->cur(), HB_UNICODE_GENERAL_CATEGORY_OTHER_LETTER); 841 } 842 } 843 c->replace_glyph_with_ligature (lig_glyph, klass); 844 845 for (unsigned int i = 1; i < count; i++) 846 { 847 while (buffer->idx < match_positions[i] && !buffer->in_error) 848 { 849 if (!is_mark_ligature) { 850 unsigned int this_comp = _hb_glyph_info_get_lig_comp (&buffer->cur()); 851 if (this_comp == 0) 852 this_comp = last_num_components; 853 unsigned int new_lig_comp = components_so_far - last_num_components + 854 MIN (this_comp, last_num_components); 855 _hb_glyph_info_set_lig_props_for_mark (&buffer->cur(), lig_id, new_lig_comp); 856 } 857 buffer->next_glyph (); 858 } 859 860 last_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur()); 861 last_num_components = _hb_glyph_info_get_lig_num_comps (&buffer->cur()); 862 components_so_far += last_num_components; 863 864 /* Skip the base glyph */ 865 buffer->idx++; 866 } 867 868 if (!is_mark_ligature && last_lig_id) { 869 /* Re-adjust components for any marks following. */ 870 for (unsigned int i = buffer->idx; i < buffer->len; i++) { 871 if (last_lig_id == _hb_glyph_info_get_lig_id (&buffer->info[i])) { 872 unsigned int this_comp = _hb_glyph_info_get_lig_comp (&buffer->info[i]); 873 if (!this_comp) 874 break; 875 unsigned int new_lig_comp = components_so_far - last_num_components + 876 MIN (this_comp, last_num_components); 877 _hb_glyph_info_set_lig_props_for_mark (&buffer->info[i], lig_id, new_lig_comp); 878 } else 879 break; 880 } 881 } 882 return_trace (true); 883 } 884 885 static inline bool match_backtrack (hb_apply_context_t *c, 886 unsigned int count, 887 const USHORT backtrack[], 888 match_func_t match_func, 889 const void *match_data) 890 { 891 TRACE_APPLY (NULL); 892 893 hb_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_context; 894 skippy_iter.reset (c->buffer->backtrack_len (), count); 895 skippy_iter.set_match_func (match_func, match_data, backtrack); 896 897 for (unsigned int i = 0; i < count; i++) 898 if (!skippy_iter.prev ()) 899 return_trace (false); 900 901 return_trace (true); 902 } 903 904 static inline bool match_lookahead (hb_apply_context_t *c, 905 unsigned int count, 906 const USHORT lookahead[], 907 match_func_t match_func, 908 const void *match_data, 909 unsigned int offset) 910 { 911 TRACE_APPLY (NULL); 912 913 hb_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_context; 914 skippy_iter.reset (c->buffer->idx + offset - 1, count); 915 skippy_iter.set_match_func (match_func, match_data, lookahead); 916 917 for (unsigned int i = 0; i < count; i++) 918 if (!skippy_iter.next ()) 919 return_trace (false); 920 921 return_trace (true); 922 } 923 924 925 926 struct LookupRecord 927 { 928 inline bool sanitize (hb_sanitize_context_t *c) const 929 { 930 TRACE_SANITIZE (this); 931 return_trace (c->check_struct (this)); 932 } 933 934 USHORT sequenceIndex; /* Index into current glyph 935 * sequence--first glyph = 0 */ 936 USHORT lookupListIndex; /* Lookup to apply to that 937 * position--zero--based */ 938 public: 939 DEFINE_SIZE_STATIC (4); 940 }; 941 942 943 template <typename context_t> 944 static inline void recurse_lookups (context_t *c, 945 unsigned int lookupCount, 946 const LookupRecord lookupRecord[] /* Array of LookupRecords--in design order */) 947 { 948 for (unsigned int i = 0; i < lookupCount; i++) 949 c->recurse (lookupRecord[i].lookupListIndex); 950 } 951 952 static inline bool apply_lookup (hb_apply_context_t *c, 953 unsigned int count, /* Including the first glyph */ 954 unsigned int match_positions[HB_MAX_CONTEXT_LENGTH], /* Including the first glyph */ 955 unsigned int lookupCount, 956 const LookupRecord lookupRecord[], /* Array of LookupRecords--in design order */ 957 unsigned int match_length) 958 { 959 TRACE_APPLY (NULL); 960 961 hb_buffer_t *buffer = c->buffer; 962 unsigned int end; 963 964 /* All positions are distance from beginning of *output* buffer. 965 * Adjust. */ 966 { 967 unsigned int bl = buffer->backtrack_len (); 968 end = bl + match_length; 969 970 int delta = bl - buffer->idx; 971 /* Convert positions to new indexing. */ 972 for (unsigned int j = 0; j < count; j++) 973 match_positions[j] += delta; 974 } 975 976 for (unsigned int i = 0; i < lookupCount && !buffer->in_error; i++) 977 { 978 unsigned int idx = lookupRecord[i].sequenceIndex; 979 if (idx >= count) 980 continue; 981 982 /* Don't recurse to ourself at same position. 983 * Note that this test is too naive, it doesn't catch longer loops. */ 984 if (idx == 0 && lookupRecord[i].lookupListIndex == c->lookup_index) 985 continue; 986 987 buffer->move_to (match_positions[idx]); 988 989 unsigned int orig_len = buffer->backtrack_len () + buffer->lookahead_len (); 990 if (!c->recurse (lookupRecord[i].lookupListIndex)) 991 continue; 992 993 unsigned int new_len = buffer->backtrack_len () + buffer->lookahead_len (); 994 int delta = new_len - orig_len; 995 996 if (!delta) 997 continue; 998 999 /* Recursed lookup changed buffer len. Adjust. */ 1000 1001 end = int (end) + delta; 1002 if (end <= match_positions[idx]) 1003 { 1004 /* End might end up being smaller than match_positions[idx] if the recursed 1005 * lookup ended up removing many items, more than we have had matched. 1006 * Just never rewind end back and get out of here. 1007 * https://bugs.chromium.org/p/chromium/issues/detail?id=659496 */ 1008 end = match_positions[idx]; 1009 /* There can't be any further changes. */ 1010 break; 1011 } 1012 1013 unsigned int next = idx + 1; /* next now is the position after the recursed lookup. */ 1014 1015 if (delta > 0) 1016 { 1017 if (unlikely (delta + count > HB_MAX_CONTEXT_LENGTH)) 1018 break; 1019 } 1020 else 1021 { 1022 /* NOTE: delta is negative. */ 1023 delta = MAX (delta, (int) next - (int) count); 1024 next -= delta; 1025 } 1026 1027 /* Shift! */ 1028 memmove (match_positions + next + delta, match_positions + next, 1029 (count - next) * sizeof (match_positions[0])); 1030 next += delta; 1031 count += delta; 1032 1033 /* Fill in new entries. */ 1034 for (unsigned int j = idx + 1; j < next; j++) 1035 match_positions[j] = match_positions[j - 1] + 1; 1036 1037 /* And fixup the rest. */ 1038 for (; next < count; next++) 1039 match_positions[next] += delta; 1040 } 1041 1042 buffer->move_to (end); 1043 1044 return_trace (true); 1045 } 1046 1047 1048 1049 /* Contextual lookups */ 1050 1051 struct ContextClosureLookupContext 1052 { 1053 ContextClosureFuncs funcs; 1054 const void *intersects_data; 1055 }; 1056 1057 struct ContextCollectGlyphsLookupContext 1058 { 1059 ContextCollectGlyphsFuncs funcs; 1060 const void *collect_data; 1061 }; 1062 1063 struct ContextApplyLookupContext 1064 { 1065 ContextApplyFuncs funcs; 1066 const void *match_data; 1067 }; 1068 1069 static inline void context_closure_lookup (hb_closure_context_t *c, 1070 unsigned int inputCount, /* Including the first glyph (not matched) */ 1071 const USHORT input[], /* Array of input values--start with second glyph */ 1072 unsigned int lookupCount, 1073 const LookupRecord lookupRecord[], 1074 ContextClosureLookupContext &lookup_context) 1075 { 1076 if (intersects_array (c, 1077 inputCount ? inputCount - 1 : 0, input, 1078 lookup_context.funcs.intersects, lookup_context.intersects_data)) 1079 recurse_lookups (c, 1080 lookupCount, lookupRecord); 1081 } 1082 1083 static inline void context_collect_glyphs_lookup (hb_collect_glyphs_context_t *c, 1084 unsigned int inputCount, /* Including the first glyph (not matched) */ 1085 const USHORT input[], /* Array of input values--start with second glyph */ 1086 unsigned int lookupCount, 1087 const LookupRecord lookupRecord[], 1088 ContextCollectGlyphsLookupContext &lookup_context) 1089 { 1090 collect_array (c, c->input, 1091 inputCount ? inputCount - 1 : 0, input, 1092 lookup_context.funcs.collect, lookup_context.collect_data); 1093 recurse_lookups (c, 1094 lookupCount, lookupRecord); 1095 } 1096 1097 static inline bool context_would_apply_lookup (hb_would_apply_context_t *c, 1098 unsigned int inputCount, /* Including the first glyph (not matched) */ 1099 const USHORT input[], /* Array of input values--start with second glyph */ 1100 unsigned int lookupCount HB_UNUSED, 1101 const LookupRecord lookupRecord[] HB_UNUSED, 1102 ContextApplyLookupContext &lookup_context) 1103 { 1104 return would_match_input (c, 1105 inputCount, input, 1106 lookup_context.funcs.match, lookup_context.match_data); 1107 } 1108 static inline bool context_apply_lookup (hb_apply_context_t *c, 1109 unsigned int inputCount, /* Including the first glyph (not matched) */ 1110 const USHORT input[], /* Array of input values--start with second glyph */ 1111 unsigned int lookupCount, 1112 const LookupRecord lookupRecord[], 1113 ContextApplyLookupContext &lookup_context) 1114 { 1115 unsigned int match_length = 0; 1116 unsigned int match_positions[HB_MAX_CONTEXT_LENGTH]; 1117 return match_input (c, 1118 inputCount, input, 1119 lookup_context.funcs.match, lookup_context.match_data, 1120 &match_length, match_positions) 1121 && apply_lookup (c, 1122 inputCount, match_positions, 1123 lookupCount, lookupRecord, 1124 match_length); 1125 } 1126 1127 struct Rule 1128 { 1129 inline void closure (hb_closure_context_t *c, ContextClosureLookupContext &lookup_context) const 1130 { 1131 TRACE_CLOSURE (this); 1132 const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (inputZ, inputZ[0].static_size * (inputCount ? inputCount - 1 : 0)); 1133 context_closure_lookup (c, 1134 inputCount, inputZ, 1135 lookupCount, lookupRecord, 1136 lookup_context); 1137 } 1138 1139 inline void collect_glyphs (hb_collect_glyphs_context_t *c, ContextCollectGlyphsLookupContext &lookup_context) const 1140 { 1141 TRACE_COLLECT_GLYPHS (this); 1142 const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (inputZ, inputZ[0].static_size * (inputCount ? inputCount - 1 : 0)); 1143 context_collect_glyphs_lookup (c, 1144 inputCount, inputZ, 1145 lookupCount, lookupRecord, 1146 lookup_context); 1147 } 1148 1149 inline bool would_apply (hb_would_apply_context_t *c, ContextApplyLookupContext &lookup_context) const 1150 { 1151 TRACE_WOULD_APPLY (this); 1152 const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (inputZ, inputZ[0].static_size * (inputCount ? inputCount - 1 : 0)); 1153 return_trace (context_would_apply_lookup (c, inputCount, inputZ, lookupCount, lookupRecord, lookup_context)); 1154 } 1155 1156 inline bool apply (hb_apply_context_t *c, ContextApplyLookupContext &lookup_context) const 1157 { 1158 TRACE_APPLY (this); 1159 const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (inputZ, inputZ[0].static_size * (inputCount ? inputCount - 1 : 0)); 1160 return_trace (context_apply_lookup (c, inputCount, inputZ, lookupCount, lookupRecord, lookup_context)); 1161 } 1162 1163 public: 1164 inline bool sanitize (hb_sanitize_context_t *c) const 1165 { 1166 TRACE_SANITIZE (this); 1167 return inputCount.sanitize (c) 1168 && lookupCount.sanitize (c) 1169 && c->check_range (inputZ, 1170 inputZ[0].static_size * inputCount 1171 + lookupRecordX[0].static_size * lookupCount); 1172 } 1173 1174 protected: 1175 USHORT inputCount; /* Total number of glyphs in input 1176 * glyph sequence--includes the first 1177 * glyph */ 1178 USHORT lookupCount; /* Number of LookupRecords */ 1179 USHORT inputZ[VAR]; /* Array of match inputs--start with 1180 * second glyph */ 1181 LookupRecord lookupRecordX[VAR]; /* Array of LookupRecords--in 1182 * design order */ 1183 public: 1184 DEFINE_SIZE_ARRAY2 (4, inputZ, lookupRecordX); 1185 }; 1186 1187 struct RuleSet 1188 { 1189 inline void closure (hb_closure_context_t *c, ContextClosureLookupContext &lookup_context) const 1190 { 1191 TRACE_CLOSURE (this); 1192 unsigned int num_rules = rule.len; 1193 for (unsigned int i = 0; i < num_rules; i++) 1194 (this+rule[i]).closure (c, lookup_context); 1195 } 1196 1197 inline void collect_glyphs (hb_collect_glyphs_context_t *c, ContextCollectGlyphsLookupContext &lookup_context) const 1198 { 1199 TRACE_COLLECT_GLYPHS (this); 1200 unsigned int num_rules = rule.len; 1201 for (unsigned int i = 0; i < num_rules; i++) 1202 (this+rule[i]).collect_glyphs (c, lookup_context); 1203 } 1204 1205 inline bool would_apply (hb_would_apply_context_t *c, ContextApplyLookupContext &lookup_context) const 1206 { 1207 TRACE_WOULD_APPLY (this); 1208 unsigned int num_rules = rule.len; 1209 for (unsigned int i = 0; i < num_rules; i++) 1210 { 1211 if ((this+rule[i]).would_apply (c, lookup_context)) 1212 return_trace (true); 1213 } 1214 return_trace (false); 1215 } 1216 1217 inline bool apply (hb_apply_context_t *c, ContextApplyLookupContext &lookup_context) const 1218 { 1219 TRACE_APPLY (this); 1220 unsigned int num_rules = rule.len; 1221 for (unsigned int i = 0; i < num_rules; i++) 1222 { 1223 if ((this+rule[i]).apply (c, lookup_context)) 1224 return_trace (true); 1225 } 1226 return_trace (false); 1227 } 1228 1229 inline bool sanitize (hb_sanitize_context_t *c) const 1230 { 1231 TRACE_SANITIZE (this); 1232 return_trace (rule.sanitize (c, this)); 1233 } 1234 1235 protected: 1236 OffsetArrayOf<Rule> 1237 rule; /* Array of Rule tables 1238 * ordered by preference */ 1239 public: 1240 DEFINE_SIZE_ARRAY (2, rule); 1241 }; 1242 1243 1244 struct ContextFormat1 1245 { 1246 inline void closure (hb_closure_context_t *c) const 1247 { 1248 TRACE_CLOSURE (this); 1249 1250 const Coverage &cov = (this+coverage); 1251 1252 struct ContextClosureLookupContext lookup_context = { 1253 {intersects_glyph}, 1254 NULL 1255 }; 1256 1257 unsigned int count = ruleSet.len; 1258 for (unsigned int i = 0; i < count; i++) 1259 if (cov.intersects_coverage (c->glyphs, i)) { 1260 const RuleSet &rule_set = this+ruleSet[i]; 1261 rule_set.closure (c, lookup_context); 1262 } 1263 } 1264 1265 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 1266 { 1267 TRACE_COLLECT_GLYPHS (this); 1268 (this+coverage).add_coverage (c->input); 1269 1270 struct ContextCollectGlyphsLookupContext lookup_context = { 1271 {collect_glyph}, 1272 NULL 1273 }; 1274 1275 unsigned int count = ruleSet.len; 1276 for (unsigned int i = 0; i < count; i++) 1277 (this+ruleSet[i]).collect_glyphs (c, lookup_context); 1278 } 1279 1280 inline bool would_apply (hb_would_apply_context_t *c) const 1281 { 1282 TRACE_WOULD_APPLY (this); 1283 1284 const RuleSet &rule_set = this+ruleSet[(this+coverage).get_coverage (c->glyphs[0])]; 1285 struct ContextApplyLookupContext lookup_context = { 1286 {match_glyph}, 1287 NULL 1288 }; 1289 return_trace (rule_set.would_apply (c, lookup_context)); 1290 } 1291 1292 inline const Coverage &get_coverage (void) const 1293 { 1294 return this+coverage; 1295 } 1296 1297 inline bool apply (hb_apply_context_t *c) const 1298 { 1299 TRACE_APPLY (this); 1300 unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint); 1301 if (likely (index == NOT_COVERED)) 1302 return_trace (false); 1303 1304 const RuleSet &rule_set = this+ruleSet[index]; 1305 struct ContextApplyLookupContext lookup_context = { 1306 {match_glyph}, 1307 NULL 1308 }; 1309 return_trace (rule_set.apply (c, lookup_context)); 1310 } 1311 1312 inline bool sanitize (hb_sanitize_context_t *c) const 1313 { 1314 TRACE_SANITIZE (this); 1315 return_trace (coverage.sanitize (c, this) && ruleSet.sanitize (c, this)); 1316 } 1317 1318 protected: 1319 USHORT format; /* Format identifier--format = 1 */ 1320 OffsetTo<Coverage> 1321 coverage; /* Offset to Coverage table--from 1322 * beginning of table */ 1323 OffsetArrayOf<RuleSet> 1324 ruleSet; /* Array of RuleSet tables 1325 * ordered by Coverage Index */ 1326 public: 1327 DEFINE_SIZE_ARRAY (6, ruleSet); 1328 }; 1329 1330 1331 struct ContextFormat2 1332 { 1333 inline void closure (hb_closure_context_t *c) const 1334 { 1335 TRACE_CLOSURE (this); 1336 if (!(this+coverage).intersects (c->glyphs)) 1337 return; 1338 1339 const ClassDef &class_def = this+classDef; 1340 1341 struct ContextClosureLookupContext lookup_context = { 1342 {intersects_class}, 1343 &class_def 1344 }; 1345 1346 unsigned int count = ruleSet.len; 1347 for (unsigned int i = 0; i < count; i++) 1348 if (class_def.intersects_class (c->glyphs, i)) { 1349 const RuleSet &rule_set = this+ruleSet[i]; 1350 rule_set.closure (c, lookup_context); 1351 } 1352 } 1353 1354 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 1355 { 1356 TRACE_COLLECT_GLYPHS (this); 1357 (this+coverage).add_coverage (c->input); 1358 1359 const ClassDef &class_def = this+classDef; 1360 struct ContextCollectGlyphsLookupContext lookup_context = { 1361 {collect_class}, 1362 &class_def 1363 }; 1364 1365 unsigned int count = ruleSet.len; 1366 for (unsigned int i = 0; i < count; i++) 1367 (this+ruleSet[i]).collect_glyphs (c, lookup_context); 1368 } 1369 1370 inline bool would_apply (hb_would_apply_context_t *c) const 1371 { 1372 TRACE_WOULD_APPLY (this); 1373 1374 const ClassDef &class_def = this+classDef; 1375 unsigned int index = class_def.get_class (c->glyphs[0]); 1376 const RuleSet &rule_set = this+ruleSet[index]; 1377 struct ContextApplyLookupContext lookup_context = { 1378 {match_class}, 1379 &class_def 1380 }; 1381 return_trace (rule_set.would_apply (c, lookup_context)); 1382 } 1383 1384 inline const Coverage &get_coverage (void) const 1385 { 1386 return this+coverage; 1387 } 1388 1389 inline bool apply (hb_apply_context_t *c) const 1390 { 1391 TRACE_APPLY (this); 1392 unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint); 1393 if (likely (index == NOT_COVERED)) return_trace (false); 1394 1395 const ClassDef &class_def = this+classDef; 1396 index = class_def.get_class (c->buffer->cur().codepoint); 1397 const RuleSet &rule_set = this+ruleSet[index]; 1398 struct ContextApplyLookupContext lookup_context = { 1399 {match_class}, 1400 &class_def 1401 }; 1402 return_trace (rule_set.apply (c, lookup_context)); 1403 } 1404 1405 inline bool sanitize (hb_sanitize_context_t *c) const 1406 { 1407 TRACE_SANITIZE (this); 1408 return_trace (coverage.sanitize (c, this) && classDef.sanitize (c, this) && ruleSet.sanitize (c, this)); 1409 } 1410 1411 protected: 1412 USHORT format; /* Format identifier--format = 2 */ 1413 OffsetTo<Coverage> 1414 coverage; /* Offset to Coverage table--from 1415 * beginning of table */ 1416 OffsetTo<ClassDef> 1417 classDef; /* Offset to glyph ClassDef table--from 1418 * beginning of table */ 1419 OffsetArrayOf<RuleSet> 1420 ruleSet; /* Array of RuleSet tables 1421 * ordered by class */ 1422 public: 1423 DEFINE_SIZE_ARRAY (8, ruleSet); 1424 }; 1425 1426 1427 struct ContextFormat3 1428 { 1429 inline void closure (hb_closure_context_t *c) const 1430 { 1431 TRACE_CLOSURE (this); 1432 if (!(this+coverageZ[0]).intersects (c->glyphs)) 1433 return; 1434 1435 const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (coverageZ, coverageZ[0].static_size * glyphCount); 1436 struct ContextClosureLookupContext lookup_context = { 1437 {intersects_coverage}, 1438 this 1439 }; 1440 context_closure_lookup (c, 1441 glyphCount, (const USHORT *) (coverageZ + 1), 1442 lookupCount, lookupRecord, 1443 lookup_context); 1444 } 1445 1446 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 1447 { 1448 TRACE_COLLECT_GLYPHS (this); 1449 (this+coverageZ[0]).add_coverage (c->input); 1450 1451 const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (coverageZ, coverageZ[0].static_size * glyphCount); 1452 struct ContextCollectGlyphsLookupContext lookup_context = { 1453 {collect_coverage}, 1454 this 1455 }; 1456 1457 context_collect_glyphs_lookup (c, 1458 glyphCount, (const USHORT *) (coverageZ + 1), 1459 lookupCount, lookupRecord, 1460 lookup_context); 1461 } 1462 1463 inline bool would_apply (hb_would_apply_context_t *c) const 1464 { 1465 TRACE_WOULD_APPLY (this); 1466 1467 const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (coverageZ, coverageZ[0].static_size * glyphCount); 1468 struct ContextApplyLookupContext lookup_context = { 1469 {match_coverage}, 1470 this 1471 }; 1472 return_trace (context_would_apply_lookup (c, glyphCount, (const USHORT *) (coverageZ + 1), lookupCount, lookupRecord, lookup_context)); 1473 } 1474 1475 inline const Coverage &get_coverage (void) const 1476 { 1477 return this+coverageZ[0]; 1478 } 1479 1480 inline bool apply (hb_apply_context_t *c) const 1481 { 1482 TRACE_APPLY (this); 1483 unsigned int index = (this+coverageZ[0]).get_coverage (c->buffer->cur().codepoint); 1484 if (likely (index == NOT_COVERED)) return_trace (false); 1485 1486 const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (coverageZ, coverageZ[0].static_size * glyphCount); 1487 struct ContextApplyLookupContext lookup_context = { 1488 {match_coverage}, 1489 this 1490 }; 1491 return_trace (context_apply_lookup (c, glyphCount, (const USHORT *) (coverageZ + 1), lookupCount, lookupRecord, lookup_context)); 1492 } 1493 1494 inline bool sanitize (hb_sanitize_context_t *c) const 1495 { 1496 TRACE_SANITIZE (this); 1497 if (!c->check_struct (this)) return_trace (false); 1498 unsigned int count = glyphCount; 1499 if (!count) return_trace (false); /* We want to access coverageZ[0] freely. */ 1500 if (!c->check_array (coverageZ, coverageZ[0].static_size, count)) return_trace (false); 1501 for (unsigned int i = 0; i < count; i++) 1502 if (!coverageZ[i].sanitize (c, this)) return_trace (false); 1503 const LookupRecord *lookupRecord = &StructAtOffset<LookupRecord> (coverageZ, coverageZ[0].static_size * count); 1504 return_trace (c->check_array (lookupRecord, lookupRecord[0].static_size, lookupCount)); 1505 } 1506 1507 protected: 1508 USHORT format; /* Format identifier--format = 3 */ 1509 USHORT glyphCount; /* Number of glyphs in the input glyph 1510 * sequence */ 1511 USHORT lookupCount; /* Number of LookupRecords */ 1512 OffsetTo<Coverage> 1513 coverageZ[VAR]; /* Array of offsets to Coverage 1514 * table in glyph sequence order */ 1515 LookupRecord lookupRecordX[VAR]; /* Array of LookupRecords--in 1516 * design order */ 1517 public: 1518 DEFINE_SIZE_ARRAY2 (6, coverageZ, lookupRecordX); 1519 }; 1520 1521 struct Context 1522 { 1523 template <typename context_t> 1524 inline typename context_t::return_t dispatch (context_t *c) const 1525 { 1526 TRACE_DISPATCH (this, u.format); 1527 if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); 1528 switch (u.format) { 1529 case 1: return_trace (c->dispatch (u.format1)); 1530 case 2: return_trace (c->dispatch (u.format2)); 1531 case 3: return_trace (c->dispatch (u.format3)); 1532 default:return_trace (c->default_return_value ()); 1533 } 1534 } 1535 1536 protected: 1537 union { 1538 USHORT format; /* Format identifier */ 1539 ContextFormat1 format1; 1540 ContextFormat2 format2; 1541 ContextFormat3 format3; 1542 } u; 1543 }; 1544 1545 1546 /* Chaining Contextual lookups */ 1547 1548 struct ChainContextClosureLookupContext 1549 { 1550 ContextClosureFuncs funcs; 1551 const void *intersects_data[3]; 1552 }; 1553 1554 struct ChainContextCollectGlyphsLookupContext 1555 { 1556 ContextCollectGlyphsFuncs funcs; 1557 const void *collect_data[3]; 1558 }; 1559 1560 struct ChainContextApplyLookupContext 1561 { 1562 ContextApplyFuncs funcs; 1563 const void *match_data[3]; 1564 }; 1565 1566 static inline void chain_context_closure_lookup (hb_closure_context_t *c, 1567 unsigned int backtrackCount, 1568 const USHORT backtrack[], 1569 unsigned int inputCount, /* Including the first glyph (not matched) */ 1570 const USHORT input[], /* Array of input values--start with second glyph */ 1571 unsigned int lookaheadCount, 1572 const USHORT lookahead[], 1573 unsigned int lookupCount, 1574 const LookupRecord lookupRecord[], 1575 ChainContextClosureLookupContext &lookup_context) 1576 { 1577 if (intersects_array (c, 1578 backtrackCount, backtrack, 1579 lookup_context.funcs.intersects, lookup_context.intersects_data[0]) 1580 && intersects_array (c, 1581 inputCount ? inputCount - 1 : 0, input, 1582 lookup_context.funcs.intersects, lookup_context.intersects_data[1]) 1583 && intersects_array (c, 1584 lookaheadCount, lookahead, 1585 lookup_context.funcs.intersects, lookup_context.intersects_data[2])) 1586 recurse_lookups (c, 1587 lookupCount, lookupRecord); 1588 } 1589 1590 static inline void chain_context_collect_glyphs_lookup (hb_collect_glyphs_context_t *c, 1591 unsigned int backtrackCount, 1592 const USHORT backtrack[], 1593 unsigned int inputCount, /* Including the first glyph (not matched) */ 1594 const USHORT input[], /* Array of input values--start with second glyph */ 1595 unsigned int lookaheadCount, 1596 const USHORT lookahead[], 1597 unsigned int lookupCount, 1598 const LookupRecord lookupRecord[], 1599 ChainContextCollectGlyphsLookupContext &lookup_context) 1600 { 1601 collect_array (c, c->before, 1602 backtrackCount, backtrack, 1603 lookup_context.funcs.collect, lookup_context.collect_data[0]); 1604 collect_array (c, c->input, 1605 inputCount ? inputCount - 1 : 0, input, 1606 lookup_context.funcs.collect, lookup_context.collect_data[1]); 1607 collect_array (c, c->after, 1608 lookaheadCount, lookahead, 1609 lookup_context.funcs.collect, lookup_context.collect_data[2]); 1610 recurse_lookups (c, 1611 lookupCount, lookupRecord); 1612 } 1613 1614 static inline bool chain_context_would_apply_lookup (hb_would_apply_context_t *c, 1615 unsigned int backtrackCount, 1616 const USHORT backtrack[] HB_UNUSED, 1617 unsigned int inputCount, /* Including the first glyph (not matched) */ 1618 const USHORT input[], /* Array of input values--start with second glyph */ 1619 unsigned int lookaheadCount, 1620 const USHORT lookahead[] HB_UNUSED, 1621 unsigned int lookupCount HB_UNUSED, 1622 const LookupRecord lookupRecord[] HB_UNUSED, 1623 ChainContextApplyLookupContext &lookup_context) 1624 { 1625 return (c->zero_context ? !backtrackCount && !lookaheadCount : true) 1626 && would_match_input (c, 1627 inputCount, input, 1628 lookup_context.funcs.match, lookup_context.match_data[1]); 1629 } 1630 1631 static inline bool chain_context_apply_lookup (hb_apply_context_t *c, 1632 unsigned int backtrackCount, 1633 const USHORT backtrack[], 1634 unsigned int inputCount, /* Including the first glyph (not matched) */ 1635 const USHORT input[], /* Array of input values--start with second glyph */ 1636 unsigned int lookaheadCount, 1637 const USHORT lookahead[], 1638 unsigned int lookupCount, 1639 const LookupRecord lookupRecord[], 1640 ChainContextApplyLookupContext &lookup_context) 1641 { 1642 unsigned int match_length = 0; 1643 unsigned int match_positions[HB_MAX_CONTEXT_LENGTH]; 1644 return match_input (c, 1645 inputCount, input, 1646 lookup_context.funcs.match, lookup_context.match_data[1], 1647 &match_length, match_positions) 1648 && match_backtrack (c, 1649 backtrackCount, backtrack, 1650 lookup_context.funcs.match, lookup_context.match_data[0]) 1651 && match_lookahead (c, 1652 lookaheadCount, lookahead, 1653 lookup_context.funcs.match, lookup_context.match_data[2], 1654 match_length) 1655 && apply_lookup (c, 1656 inputCount, match_positions, 1657 lookupCount, lookupRecord, 1658 match_length); 1659 } 1660 1661 struct ChainRule 1662 { 1663 inline void closure (hb_closure_context_t *c, ChainContextClosureLookupContext &lookup_context) const 1664 { 1665 TRACE_CLOSURE (this); 1666 const HeadlessArrayOf<USHORT> &input = StructAfter<HeadlessArrayOf<USHORT> > (backtrack); 1667 const ArrayOf<USHORT> &lookahead = StructAfter<ArrayOf<USHORT> > (input); 1668 const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead); 1669 chain_context_closure_lookup (c, 1670 backtrack.len, backtrack.array, 1671 input.len, input.array, 1672 lookahead.len, lookahead.array, 1673 lookup.len, lookup.array, 1674 lookup_context); 1675 } 1676 1677 inline void collect_glyphs (hb_collect_glyphs_context_t *c, ChainContextCollectGlyphsLookupContext &lookup_context) const 1678 { 1679 TRACE_COLLECT_GLYPHS (this); 1680 const HeadlessArrayOf<USHORT> &input = StructAfter<HeadlessArrayOf<USHORT> > (backtrack); 1681 const ArrayOf<USHORT> &lookahead = StructAfter<ArrayOf<USHORT> > (input); 1682 const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead); 1683 chain_context_collect_glyphs_lookup (c, 1684 backtrack.len, backtrack.array, 1685 input.len, input.array, 1686 lookahead.len, lookahead.array, 1687 lookup.len, lookup.array, 1688 lookup_context); 1689 } 1690 1691 inline bool would_apply (hb_would_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const 1692 { 1693 TRACE_WOULD_APPLY (this); 1694 const HeadlessArrayOf<USHORT> &input = StructAfter<HeadlessArrayOf<USHORT> > (backtrack); 1695 const ArrayOf<USHORT> &lookahead = StructAfter<ArrayOf<USHORT> > (input); 1696 const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead); 1697 return_trace (chain_context_would_apply_lookup (c, 1698 backtrack.len, backtrack.array, 1699 input.len, input.array, 1700 lookahead.len, lookahead.array, lookup.len, 1701 lookup.array, lookup_context)); 1702 } 1703 1704 inline bool apply (hb_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const 1705 { 1706 TRACE_APPLY (this); 1707 const HeadlessArrayOf<USHORT> &input = StructAfter<HeadlessArrayOf<USHORT> > (backtrack); 1708 const ArrayOf<USHORT> &lookahead = StructAfter<ArrayOf<USHORT> > (input); 1709 const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead); 1710 return_trace (chain_context_apply_lookup (c, 1711 backtrack.len, backtrack.array, 1712 input.len, input.array, 1713 lookahead.len, lookahead.array, lookup.len, 1714 lookup.array, lookup_context)); 1715 } 1716 1717 inline bool sanitize (hb_sanitize_context_t *c) const 1718 { 1719 TRACE_SANITIZE (this); 1720 if (!backtrack.sanitize (c)) return_trace (false); 1721 const HeadlessArrayOf<USHORT> &input = StructAfter<HeadlessArrayOf<USHORT> > (backtrack); 1722 if (!input.sanitize (c)) return_trace (false); 1723 const ArrayOf<USHORT> &lookahead = StructAfter<ArrayOf<USHORT> > (input); 1724 if (!lookahead.sanitize (c)) return_trace (false); 1725 const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead); 1726 return_trace (lookup.sanitize (c)); 1727 } 1728 1729 protected: 1730 ArrayOf<USHORT> 1731 backtrack; /* Array of backtracking values 1732 * (to be matched before the input 1733 * sequence) */ 1734 HeadlessArrayOf<USHORT> 1735 inputX; /* Array of input values (start with 1736 * second glyph) */ 1737 ArrayOf<USHORT> 1738 lookaheadX; /* Array of lookahead values's (to be 1739 * matched after the input sequence) */ 1740 ArrayOf<LookupRecord> 1741 lookupX; /* Array of LookupRecords--in 1742 * design order) */ 1743 public: 1744 DEFINE_SIZE_MIN (8); 1745 }; 1746 1747 struct ChainRuleSet 1748 { 1749 inline void closure (hb_closure_context_t *c, ChainContextClosureLookupContext &lookup_context) const 1750 { 1751 TRACE_CLOSURE (this); 1752 unsigned int num_rules = rule.len; 1753 for (unsigned int i = 0; i < num_rules; i++) 1754 (this+rule[i]).closure (c, lookup_context); 1755 } 1756 1757 inline void collect_glyphs (hb_collect_glyphs_context_t *c, ChainContextCollectGlyphsLookupContext &lookup_context) const 1758 { 1759 TRACE_COLLECT_GLYPHS (this); 1760 unsigned int num_rules = rule.len; 1761 for (unsigned int i = 0; i < num_rules; i++) 1762 (this+rule[i]).collect_glyphs (c, lookup_context); 1763 } 1764 1765 inline bool would_apply (hb_would_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const 1766 { 1767 TRACE_WOULD_APPLY (this); 1768 unsigned int num_rules = rule.len; 1769 for (unsigned int i = 0; i < num_rules; i++) 1770 if ((this+rule[i]).would_apply (c, lookup_context)) 1771 return_trace (true); 1772 1773 return_trace (false); 1774 } 1775 1776 inline bool apply (hb_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const 1777 { 1778 TRACE_APPLY (this); 1779 unsigned int num_rules = rule.len; 1780 for (unsigned int i = 0; i < num_rules; i++) 1781 if ((this+rule[i]).apply (c, lookup_context)) 1782 return_trace (true); 1783 1784 return_trace (false); 1785 } 1786 1787 inline bool sanitize (hb_sanitize_context_t *c) const 1788 { 1789 TRACE_SANITIZE (this); 1790 return_trace (rule.sanitize (c, this)); 1791 } 1792 1793 protected: 1794 OffsetArrayOf<ChainRule> 1795 rule; /* Array of ChainRule tables 1796 * ordered by preference */ 1797 public: 1798 DEFINE_SIZE_ARRAY (2, rule); 1799 }; 1800 1801 struct ChainContextFormat1 1802 { 1803 inline void closure (hb_closure_context_t *c) const 1804 { 1805 TRACE_CLOSURE (this); 1806 const Coverage &cov = (this+coverage); 1807 1808 struct ChainContextClosureLookupContext lookup_context = { 1809 {intersects_glyph}, 1810 {NULL, NULL, NULL} 1811 }; 1812 1813 unsigned int count = ruleSet.len; 1814 for (unsigned int i = 0; i < count; i++) 1815 if (cov.intersects_coverage (c->glyphs, i)) { 1816 const ChainRuleSet &rule_set = this+ruleSet[i]; 1817 rule_set.closure (c, lookup_context); 1818 } 1819 } 1820 1821 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 1822 { 1823 TRACE_COLLECT_GLYPHS (this); 1824 (this+coverage).add_coverage (c->input); 1825 1826 struct ChainContextCollectGlyphsLookupContext lookup_context = { 1827 {collect_glyph}, 1828 {NULL, NULL, NULL} 1829 }; 1830 1831 unsigned int count = ruleSet.len; 1832 for (unsigned int i = 0; i < count; i++) 1833 (this+ruleSet[i]).collect_glyphs (c, lookup_context); 1834 } 1835 1836 inline bool would_apply (hb_would_apply_context_t *c) const 1837 { 1838 TRACE_WOULD_APPLY (this); 1839 1840 const ChainRuleSet &rule_set = this+ruleSet[(this+coverage).get_coverage (c->glyphs[0])]; 1841 struct ChainContextApplyLookupContext lookup_context = { 1842 {match_glyph}, 1843 {NULL, NULL, NULL} 1844 }; 1845 return_trace (rule_set.would_apply (c, lookup_context)); 1846 } 1847 1848 inline const Coverage &get_coverage (void) const 1849 { 1850 return this+coverage; 1851 } 1852 1853 inline bool apply (hb_apply_context_t *c) const 1854 { 1855 TRACE_APPLY (this); 1856 unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint); 1857 if (likely (index == NOT_COVERED)) return_trace (false); 1858 1859 const ChainRuleSet &rule_set = this+ruleSet[index]; 1860 struct ChainContextApplyLookupContext lookup_context = { 1861 {match_glyph}, 1862 {NULL, NULL, NULL} 1863 }; 1864 return_trace (rule_set.apply (c, lookup_context)); 1865 } 1866 1867 inline bool sanitize (hb_sanitize_context_t *c) const 1868 { 1869 TRACE_SANITIZE (this); 1870 return_trace (coverage.sanitize (c, this) && ruleSet.sanitize (c, this)); 1871 } 1872 1873 protected: 1874 USHORT format; /* Format identifier--format = 1 */ 1875 OffsetTo<Coverage> 1876 coverage; /* Offset to Coverage table--from 1877 * beginning of table */ 1878 OffsetArrayOf<ChainRuleSet> 1879 ruleSet; /* Array of ChainRuleSet tables 1880 * ordered by Coverage Index */ 1881 public: 1882 DEFINE_SIZE_ARRAY (6, ruleSet); 1883 }; 1884 1885 struct ChainContextFormat2 1886 { 1887 inline void closure (hb_closure_context_t *c) const 1888 { 1889 TRACE_CLOSURE (this); 1890 if (!(this+coverage).intersects (c->glyphs)) 1891 return; 1892 1893 const ClassDef &backtrack_class_def = this+backtrackClassDef; 1894 const ClassDef &input_class_def = this+inputClassDef; 1895 const ClassDef &lookahead_class_def = this+lookaheadClassDef; 1896 1897 struct ChainContextClosureLookupContext lookup_context = { 1898 {intersects_class}, 1899 {&backtrack_class_def, 1900 &input_class_def, 1901 &lookahead_class_def} 1902 }; 1903 1904 unsigned int count = ruleSet.len; 1905 for (unsigned int i = 0; i < count; i++) 1906 if (input_class_def.intersects_class (c->glyphs, i)) { 1907 const ChainRuleSet &rule_set = this+ruleSet[i]; 1908 rule_set.closure (c, lookup_context); 1909 } 1910 } 1911 1912 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 1913 { 1914 TRACE_COLLECT_GLYPHS (this); 1915 (this+coverage).add_coverage (c->input); 1916 1917 const ClassDef &backtrack_class_def = this+backtrackClassDef; 1918 const ClassDef &input_class_def = this+inputClassDef; 1919 const ClassDef &lookahead_class_def = this+lookaheadClassDef; 1920 1921 struct ChainContextCollectGlyphsLookupContext lookup_context = { 1922 {collect_class}, 1923 {&backtrack_class_def, 1924 &input_class_def, 1925 &lookahead_class_def} 1926 }; 1927 1928 unsigned int count = ruleSet.len; 1929 for (unsigned int i = 0; i < count; i++) 1930 (this+ruleSet[i]).collect_glyphs (c, lookup_context); 1931 } 1932 1933 inline bool would_apply (hb_would_apply_context_t *c) const 1934 { 1935 TRACE_WOULD_APPLY (this); 1936 1937 const ClassDef &backtrack_class_def = this+backtrackClassDef; 1938 const ClassDef &input_class_def = this+inputClassDef; 1939 const ClassDef &lookahead_class_def = this+lookaheadClassDef; 1940 1941 unsigned int index = input_class_def.get_class (c->glyphs[0]); 1942 const ChainRuleSet &rule_set = this+ruleSet[index]; 1943 struct ChainContextApplyLookupContext lookup_context = { 1944 {match_class}, 1945 {&backtrack_class_def, 1946 &input_class_def, 1947 &lookahead_class_def} 1948 }; 1949 return_trace (rule_set.would_apply (c, lookup_context)); 1950 } 1951 1952 inline const Coverage &get_coverage (void) const 1953 { 1954 return this+coverage; 1955 } 1956 1957 inline bool apply (hb_apply_context_t *c) const 1958 { 1959 TRACE_APPLY (this); 1960 unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint); 1961 if (likely (index == NOT_COVERED)) return_trace (false); 1962 1963 const ClassDef &backtrack_class_def = this+backtrackClassDef; 1964 const ClassDef &input_class_def = this+inputClassDef; 1965 const ClassDef &lookahead_class_def = this+lookaheadClassDef; 1966 1967 index = input_class_def.get_class (c->buffer->cur().codepoint); 1968 const ChainRuleSet &rule_set = this+ruleSet[index]; 1969 struct ChainContextApplyLookupContext lookup_context = { 1970 {match_class}, 1971 {&backtrack_class_def, 1972 &input_class_def, 1973 &lookahead_class_def} 1974 }; 1975 return_trace (rule_set.apply (c, lookup_context)); 1976 } 1977 1978 inline bool sanitize (hb_sanitize_context_t *c) const 1979 { 1980 TRACE_SANITIZE (this); 1981 return_trace (coverage.sanitize (c, this) && 1982 backtrackClassDef.sanitize (c, this) && 1983 inputClassDef.sanitize (c, this) && 1984 lookaheadClassDef.sanitize (c, this) && 1985 ruleSet.sanitize (c, this)); 1986 } 1987 1988 protected: 1989 USHORT format; /* Format identifier--format = 2 */ 1990 OffsetTo<Coverage> 1991 coverage; /* Offset to Coverage table--from 1992 * beginning of table */ 1993 OffsetTo<ClassDef> 1994 backtrackClassDef; /* Offset to glyph ClassDef table 1995 * containing backtrack sequence 1996 * data--from beginning of table */ 1997 OffsetTo<ClassDef> 1998 inputClassDef; /* Offset to glyph ClassDef 1999 * table containing input sequence 2000 * data--from beginning of table */ 2001 OffsetTo<ClassDef> 2002 lookaheadClassDef; /* Offset to glyph ClassDef table 2003 * containing lookahead sequence 2004 * data--from beginning of table */ 2005 OffsetArrayOf<ChainRuleSet> 2006 ruleSet; /* Array of ChainRuleSet tables 2007 * ordered by class */ 2008 public: 2009 DEFINE_SIZE_ARRAY (12, ruleSet); 2010 }; 2011 2012 struct ChainContextFormat3 2013 { 2014 inline void closure (hb_closure_context_t *c) const 2015 { 2016 TRACE_CLOSURE (this); 2017 const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack); 2018 2019 if (!(this+input[0]).intersects (c->glyphs)) 2020 return; 2021 2022 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (input); 2023 const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead); 2024 struct ChainContextClosureLookupContext lookup_context = { 2025 {intersects_coverage}, 2026 {this, this, this} 2027 }; 2028 chain_context_closure_lookup (c, 2029 backtrack.len, (const USHORT *) backtrack.array, 2030 input.len, (const USHORT *) input.array + 1, 2031 lookahead.len, (const USHORT *) lookahead.array, 2032 lookup.len, lookup.array, 2033 lookup_context); 2034 } 2035 2036 inline void collect_glyphs (hb_collect_glyphs_context_t *c) const 2037 { 2038 TRACE_COLLECT_GLYPHS (this); 2039 const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack); 2040 2041 (this+input[0]).add_coverage (c->input); 2042 2043 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (input); 2044 const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead); 2045 struct ChainContextCollectGlyphsLookupContext lookup_context = { 2046 {collect_coverage}, 2047 {this, this, this} 2048 }; 2049 chain_context_collect_glyphs_lookup (c, 2050 backtrack.len, (const USHORT *) backtrack.array, 2051 input.len, (const USHORT *) input.array + 1, 2052 lookahead.len, (const USHORT *) lookahead.array, 2053 lookup.len, lookup.array, 2054 lookup_context); 2055 } 2056 2057 inline bool would_apply (hb_would_apply_context_t *c) const 2058 { 2059 TRACE_WOULD_APPLY (this); 2060 2061 const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack); 2062 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (input); 2063 const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead); 2064 struct ChainContextApplyLookupContext lookup_context = { 2065 {match_coverage}, 2066 {this, this, this} 2067 }; 2068 return_trace (chain_context_would_apply_lookup (c, 2069 backtrack.len, (const USHORT *) backtrack.array, 2070 input.len, (const USHORT *) input.array + 1, 2071 lookahead.len, (const USHORT *) lookahead.array, 2072 lookup.len, lookup.array, lookup_context)); 2073 } 2074 2075 inline const Coverage &get_coverage (void) const 2076 { 2077 const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack); 2078 return this+input[0]; 2079 } 2080 2081 inline bool apply (hb_apply_context_t *c) const 2082 { 2083 TRACE_APPLY (this); 2084 const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack); 2085 2086 unsigned int index = (this+input[0]).get_coverage (c->buffer->cur().codepoint); 2087 if (likely (index == NOT_COVERED)) return_trace (false); 2088 2089 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (input); 2090 const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead); 2091 struct ChainContextApplyLookupContext lookup_context = { 2092 {match_coverage}, 2093 {this, this, this} 2094 }; 2095 return_trace (chain_context_apply_lookup (c, 2096 backtrack.len, (const USHORT *) backtrack.array, 2097 input.len, (const USHORT *) input.array + 1, 2098 lookahead.len, (const USHORT *) lookahead.array, 2099 lookup.len, lookup.array, lookup_context)); 2100 } 2101 2102 inline bool sanitize (hb_sanitize_context_t *c) const 2103 { 2104 TRACE_SANITIZE (this); 2105 if (!backtrack.sanitize (c, this)) return_trace (false); 2106 const OffsetArrayOf<Coverage> &input = StructAfter<OffsetArrayOf<Coverage> > (backtrack); 2107 if (!input.sanitize (c, this)) return_trace (false); 2108 if (!input.len) return_trace (false); /* To be consistent with Context. */ 2109 const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (input); 2110 if (!lookahead.sanitize (c, this)) return_trace (false); 2111 const ArrayOf<LookupRecord> &lookup = StructAfter<ArrayOf<LookupRecord> > (lookahead); 2112 return_trace (lookup.sanitize (c)); 2113 } 2114 2115 protected: 2116 USHORT format; /* Format identifier--format = 3 */ 2117 OffsetArrayOf<Coverage> 2118 backtrack; /* Array of coverage tables 2119 * in backtracking sequence, in glyph 2120 * sequence order */ 2121 OffsetArrayOf<Coverage> 2122 inputX ; /* Array of coverage 2123 * tables in input sequence, in glyph 2124 * sequence order */ 2125 OffsetArrayOf<Coverage> 2126 lookaheadX; /* Array of coverage tables 2127 * in lookahead sequence, in glyph 2128 * sequence order */ 2129 ArrayOf<LookupRecord> 2130 lookupX; /* Array of LookupRecords--in 2131 * design order) */ 2132 public: 2133 DEFINE_SIZE_MIN (10); 2134 }; 2135 2136 struct ChainContext 2137 { 2138 template <typename context_t> 2139 inline typename context_t::return_t dispatch (context_t *c) const 2140 { 2141 TRACE_DISPATCH (this, u.format); 2142 if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); 2143 switch (u.format) { 2144 case 1: return_trace (c->dispatch (u.format1)); 2145 case 2: return_trace (c->dispatch (u.format2)); 2146 case 3: return_trace (c->dispatch (u.format3)); 2147 default:return_trace (c->default_return_value ()); 2148 } 2149 } 2150 2151 protected: 2152 union { 2153 USHORT format; /* Format identifier */ 2154 ChainContextFormat1 format1; 2155 ChainContextFormat2 format2; 2156 ChainContextFormat3 format3; 2157 } u; 2158 }; 2159 2160 2161 template <typename T> 2162 struct ExtensionFormat1 2163 { 2164 inline unsigned int get_type (void) const { return extensionLookupType; } 2165 2166 template <typename X> 2167 inline const X& get_subtable (void) const 2168 { 2169 unsigned int offset = extensionOffset; 2170 if (unlikely (!offset)) return Null(typename T::LookupSubTable); 2171 return StructAtOffset<typename T::LookupSubTable> (this, offset); 2172 } 2173 2174 template <typename context_t> 2175 inline typename context_t::return_t dispatch (context_t *c) const 2176 { 2177 TRACE_DISPATCH (this, format); 2178 if (unlikely (!c->may_dispatch (this, this))) return_trace (c->no_dispatch_return_value ()); 2179 return_trace (get_subtable<typename T::LookupSubTable> ().dispatch (c, get_type ())); 2180 } 2181 2182 /* This is called from may_dispatch() above with hb_sanitize_context_t. */ 2183 inline bool sanitize (hb_sanitize_context_t *c) const 2184 { 2185 TRACE_SANITIZE (this); 2186 return_trace (c->check_struct (this) && extensionOffset != 0); 2187 } 2188 2189 protected: 2190 USHORT format; /* Format identifier. Set to 1. */ 2191 USHORT extensionLookupType; /* Lookup type of subtable referenced 2192 * by ExtensionOffset (i.e. the 2193 * extension subtable). */ 2194 ULONG extensionOffset; /* Offset to the extension subtable, 2195 * of lookup type subtable. */ 2196 public: 2197 DEFINE_SIZE_STATIC (8); 2198 }; 2199 2200 template <typename T> 2201 struct Extension 2202 { 2203 inline unsigned int get_type (void) const 2204 { 2205 switch (u.format) { 2206 case 1: return u.format1.get_type (); 2207 default:return 0; 2208 } 2209 } 2210 template <typename X> 2211 inline const X& get_subtable (void) const 2212 { 2213 switch (u.format) { 2214 case 1: return u.format1.template get_subtable<typename T::LookupSubTable> (); 2215 default:return Null(typename T::LookupSubTable); 2216 } 2217 } 2218 2219 template <typename context_t> 2220 inline typename context_t::return_t dispatch (context_t *c) const 2221 { 2222 TRACE_DISPATCH (this, u.format); 2223 if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ()); 2224 switch (u.format) { 2225 case 1: return_trace (u.format1.dispatch (c)); 2226 default:return_trace (c->default_return_value ()); 2227 } 2228 } 2229 2230 protected: 2231 union { 2232 USHORT format; /* Format identifier */ 2233 ExtensionFormat1<T> format1; 2234 } u; 2235 }; 2236 2237 2238 /* 2239 * GSUB/GPOS Common 2240 */ 2241 2242 struct GSUBGPOS 2243 { 2244 static const hb_tag_t GSUBTag = HB_OT_TAG_GSUB; 2245 static const hb_tag_t GPOSTag = HB_OT_TAG_GPOS; 2246 2247 inline unsigned int get_script_count (void) const 2248 { return (this+scriptList).len; } 2249 inline const Tag& get_script_tag (unsigned int i) const 2250 { return (this+scriptList).get_tag (i); } 2251 inline unsigned int get_script_tags (unsigned int start_offset, 2252 unsigned int *script_count /* IN/OUT */, 2253 hb_tag_t *script_tags /* OUT */) const 2254 { return (this+scriptList).get_tags (start_offset, script_count, script_tags); } 2255 inline const Script& get_script (unsigned int i) const 2256 { return (this+scriptList)[i]; } 2257 inline bool find_script_index (hb_tag_t tag, unsigned int *index) const 2258 { return (this+scriptList).find_index (tag, index); } 2259 2260 inline unsigned int get_feature_count (void) const 2261 { return (this+featureList).len; } 2262 inline hb_tag_t get_feature_tag (unsigned int i) const 2263 { return i == Index::NOT_FOUND_INDEX ? HB_TAG_NONE : (this+featureList).get_tag (i); } 2264 inline unsigned int get_feature_tags (unsigned int start_offset, 2265 unsigned int *feature_count /* IN/OUT */, 2266 hb_tag_t *feature_tags /* OUT */) const 2267 { return (this+featureList).get_tags (start_offset, feature_count, feature_tags); } 2268 inline const Feature& get_feature (unsigned int i) const 2269 { return (this+featureList)[i]; } 2270 inline bool find_feature_index (hb_tag_t tag, unsigned int *index) const 2271 { return (this+featureList).find_index (tag, index); } 2272 2273 inline unsigned int get_lookup_count (void) const 2274 { return (this+lookupList).len; } 2275 inline const Lookup& get_lookup (unsigned int i) const 2276 { return (this+lookupList)[i]; } 2277 2278 inline bool find_variations_index (const int *coords, unsigned int num_coords, 2279 unsigned int *index) const 2280 { return (version.to_int () >= 0x00010001u ? this+featureVars : Null(FeatureVariations)) 2281 .find_index (coords, num_coords, index); } 2282 inline const Feature& get_feature_variation (unsigned int feature_index, 2283 unsigned int variations_index) const 2284 { 2285 if (FeatureVariations::NOT_FOUND_INDEX != variations_index && 2286 version.to_int () >= 0x00010001u) 2287 { 2288 const Feature *feature = (this+featureVars).find_substitute (variations_index, 2289 feature_index); 2290 if (feature) 2291 return *feature; 2292 } 2293 return get_feature (feature_index); 2294 } 2295 2296 inline bool sanitize (hb_sanitize_context_t *c) const 2297 { 2298 TRACE_SANITIZE (this); 2299 return_trace (version.sanitize (c) && 2300 likely (version.major == 1) && 2301 scriptList.sanitize (c, this) && 2302 featureList.sanitize (c, this) && 2303 lookupList.sanitize (c, this) && 2304 (version.to_int () < 0x00010001u || featureVars.sanitize (c, this))); 2305 } 2306 2307 protected: 2308 FixedVersion<>version; /* Version of the GSUB/GPOS table--initially set 2309 * to 0x00010000u */ 2310 OffsetTo<ScriptList> 2311 scriptList; /* ScriptList table */ 2312 OffsetTo<FeatureList> 2313 featureList; /* FeatureList table */ 2314 OffsetTo<LookupList> 2315 lookupList; /* LookupList table */ 2316 LOffsetTo<FeatureVariations> 2317 featureVars; /* Offset to Feature Variations 2318 table--from beginning of table 2319 * (may be NULL). Introduced 2320 * in version 0x00010001. */ 2321 public: 2322 DEFINE_SIZE_MIN (10); 2323 }; 2324 2325 2326 } /* namespace OT */ 2327 2328 2329 #endif /* HB_OT_LAYOUT_GSUBGPOS_PRIVATE_HH */ 2330
