1 /* 2 * Copyright © 2012,2017 Google, Inc. 3 * Copyright © 2021 Behdad Esfahbod 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 * Google Author(s): Behdad Esfahbod 26 */ 27 28 #ifndef HB_BIT_SET_HH 29 #define HB_BIT_SET_HH 30 31 #include "hb.hh" 32 #include "hb-bit-page.hh" 33 #include "hb-machinery.hh" 34 35 36 struct hb_bit_set_t 37 { 38 hb_bit_set_t () = default; 39 ~hb_bit_set_t () = default; 40 hb_bit_set_thb_bit_set_t41 hb_bit_set_t (const hb_bit_set_t& other) : hb_bit_set_t () { set (other); } hb_bit_set_thb_bit_set_t42 hb_bit_set_t ( hb_bit_set_t&& other) : hb_bit_set_t () { hb_swap (*this, other); } operator =hb_bit_set_t43 hb_bit_set_t& operator= (const hb_bit_set_t& other) { set (other); return *this; } operator =hb_bit_set_t44 hb_bit_set_t& operator= (hb_bit_set_t&& other) { hb_swap (*this, other); return *this; } swap(hb_bit_set_t & a,hb_bit_set_t & b)45 friend void swap (hb_bit_set_t &a, hb_bit_set_t &b) 46 { 47 if (likely (!a.successful || !b.successful)) 48 return; 49 hb_swap (a.population, b.population); 50 hb_swap (a.last_page_lookup, b.last_page_lookup); 51 hb_swap (a.page_map, b.page_map); 52 hb_swap (a.pages, b.pages); 53 } 54 inithb_bit_set_t55 void init () 56 { 57 successful = true; 58 population = 0; 59 last_page_lookup = 0; 60 page_map.init (); 61 pages.init (); 62 } finihb_bit_set_t63 void fini () 64 { 65 page_map.fini (); 66 pages.fini (); 67 } 68 69 using page_t = hb_bit_page_t; 70 struct page_map_t 71 { cmphb_bit_set_t::page_map_t72 int cmp (const page_map_t &o) const { return cmp (o.major); } cmphb_bit_set_t::page_map_t73 int cmp (uint32_t o_major) const { return (int) o_major - (int) major; } 74 75 uint32_t major; 76 uint32_t index; 77 }; 78 79 bool successful = true; /* Allocations successful */ 80 mutable unsigned int population = 0; 81 mutable hb_atomic_int_t last_page_lookup = 0; 82 hb_sorted_vector_t<page_map_t> page_map; 83 hb_vector_t<page_t> pages; 84 errhb_bit_set_t85 void err () { if (successful) successful = false; } /* TODO Remove */ in_errorhb_bit_set_t86 bool in_error () const { return !successful; } 87 resizehb_bit_set_t88 bool resize (unsigned int count, bool clear = true) 89 { 90 if (unlikely (!successful)) return false; 91 if (unlikely (!pages.resize (count, clear) || !page_map.resize (count, clear))) 92 { 93 pages.resize (page_map.length); 94 successful = false; 95 return false; 96 } 97 return true; 98 } 99 allochb_bit_set_t100 void alloc (unsigned sz) 101 { 102 sz >>= (page_t::PAGE_BITS_LOG_2 - 1); 103 pages.alloc (sz); 104 page_map.alloc (sz); 105 } 106 resethb_bit_set_t107 void reset () 108 { 109 successful = true; 110 clear (); 111 } 112 clearhb_bit_set_t113 void clear () 114 { 115 resize (0); 116 if (likely (successful)) 117 population = 0; 118 } is_emptyhb_bit_set_t119 bool is_empty () const 120 { 121 unsigned int count = pages.length; 122 for (unsigned int i = 0; i < count; i++) 123 if (!pages[i].is_empty ()) 124 return false; 125 return true; 126 } operator boolhb_bit_set_t127 explicit operator bool () const { return !is_empty (); } 128 hashhb_bit_set_t129 uint32_t hash () const 130 { 131 uint32_t h = 0; 132 for (auto &map : page_map) 133 h = h * 31 + hb_hash (map.major) + hb_hash (pages[map.index]); 134 return h; 135 } 136 137 private: dirtyhb_bit_set_t138 void dirty () { population = UINT_MAX; } 139 public: 140 addhb_bit_set_t141 void add (hb_codepoint_t g) 142 { 143 if (unlikely (!successful)) return; 144 if (unlikely (g == INVALID)) return; 145 dirty (); 146 page_t *page = page_for (g, true); if (unlikely (!page)) return; 147 page->add (g); 148 } add_rangehb_bit_set_t149 bool add_range (hb_codepoint_t a, hb_codepoint_t b) 150 { 151 if (unlikely (!successful)) return true; /* https://github.com/harfbuzz/harfbuzz/issues/657 */ 152 if (unlikely (a > b || a == INVALID || b == INVALID)) return false; 153 dirty (); 154 unsigned int ma = get_major (a); 155 unsigned int mb = get_major (b); 156 if (ma == mb) 157 { 158 page_t *page = page_for (a, true); if (unlikely (!page)) return false; 159 page->add_range (a, b); 160 } 161 else 162 { 163 page_t *page = page_for (a, true); if (unlikely (!page)) return false; 164 page->add_range (a, major_start (ma + 1) - 1); 165 166 for (unsigned int m = ma + 1; m < mb; m++) 167 { 168 page = page_for (major_start (m), true); if (unlikely (!page)) return false; 169 page->init1 (); 170 } 171 172 page = page_for (b, true); if (unlikely (!page)) return false; 173 page->add_range (major_start (mb), b); 174 } 175 return true; 176 } 177 178 template <typename T> set_arrayhb_bit_set_t179 void set_array (bool v, const T *array, unsigned int count, unsigned int stride=sizeof(T)) 180 { 181 if (unlikely (!successful)) return; 182 if (!count) return; 183 dirty (); 184 hb_codepoint_t g = *array; 185 while (count) 186 { 187 unsigned int m = get_major (g); 188 page_t *page = page_for (g, v); if (unlikely (v && !page)) return; 189 unsigned int start = major_start (m); 190 unsigned int end = major_start (m + 1); 191 do 192 { 193 if (v || page) /* The v check is to optimize out the page check if v is true. */ 194 page->set (g, v); 195 196 array = &StructAtOffsetUnaligned<T> (array, stride); 197 count--; 198 } 199 while (count && (g = *array, start <= g && g < end)); 200 } 201 } 202 203 template <typename T> add_arrayhb_bit_set_t204 void add_array (const T *array, unsigned int count, unsigned int stride=sizeof(T)) 205 { set_array (true, array, count, stride); } 206 template <typename T> add_arrayhb_bit_set_t207 void add_array (const hb_array_t<const T>& arr) { add_array (&arr, arr.len ()); } 208 209 template <typename T> del_arrayhb_bit_set_t210 void del_array (const T *array, unsigned int count, unsigned int stride=sizeof(T)) 211 { set_array (false, array, count, stride); } 212 template <typename T> del_arrayhb_bit_set_t213 void del_array (const hb_array_t<const T>& arr) { del_array (&arr, arr.len ()); } 214 215 /* Might return false if array looks unsorted. 216 * Used for faster rejection of corrupt data. */ 217 template <typename T> set_sorted_arrayhb_bit_set_t218 bool set_sorted_array (bool v, const T *array, unsigned int count, unsigned int stride=sizeof(T)) 219 { 220 if (unlikely (!successful)) return true; /* https://github.com/harfbuzz/harfbuzz/issues/657 */ 221 if (unlikely (!count)) return true; 222 dirty (); 223 hb_codepoint_t g = *array; 224 hb_codepoint_t last_g = g; 225 while (count) 226 { 227 unsigned int m = get_major (g); 228 page_t *page = page_for (g, v); if (unlikely (v && !page)) return false; 229 unsigned int end = major_start (m + 1); 230 do 231 { 232 /* If we try harder we can change the following comparison to <=; 233 * Not sure if it's worth it. */ 234 if (g < last_g) return false; 235 last_g = g; 236 237 if (v || page) /* The v check is to optimize out the page check if v is true. */ 238 page->add (g); 239 240 array = &StructAtOffsetUnaligned<T> (array, stride); 241 count--; 242 } 243 while (count && (g = *array, g < end)); 244 } 245 return true; 246 } 247 248 template <typename T> add_sorted_arrayhb_bit_set_t249 bool add_sorted_array (const T *array, unsigned int count, unsigned int stride=sizeof(T)) 250 { return set_sorted_array (true, array, count, stride); } 251 template <typename T> add_sorted_arrayhb_bit_set_t252 bool add_sorted_array (const hb_sorted_array_t<const T>& arr) { return add_sorted_array (&arr, arr.len ()); } 253 254 template <typename T> del_sorted_arrayhb_bit_set_t255 bool del_sorted_array (const T *array, unsigned int count, unsigned int stride=sizeof(T)) 256 { return set_sorted_array (false, array, count, stride); } 257 template <typename T> del_sorted_arrayhb_bit_set_t258 bool del_sorted_array (const hb_sorted_array_t<const T>& arr) { return del_sorted_array (&arr, arr.len ()); } 259 delhb_bit_set_t260 void del (hb_codepoint_t g) 261 { 262 if (unlikely (!successful)) return; 263 page_t *page = page_for (g); 264 if (!page) 265 return; 266 dirty (); 267 page->del (g); 268 } 269 270 private: del_pageshb_bit_set_t271 void del_pages (int ds, int de) 272 { 273 if (ds <= de) 274 { 275 // Pre-allocate the workspace that compact() will need so we can bail on allocation failure 276 // before attempting to rewrite the page map. 277 hb_vector_t<unsigned> compact_workspace; 278 if (unlikely (!allocate_compact_workspace (compact_workspace))) return; 279 280 unsigned int write_index = 0; 281 for (unsigned int i = 0; i < page_map.length; i++) 282 { 283 int m = (int) page_map[i].major; 284 if (m < ds || de < m) 285 page_map[write_index++] = page_map[i]; 286 } 287 compact (compact_workspace, write_index); 288 resize (write_index); 289 } 290 } 291 292 293 public: del_rangehb_bit_set_t294 void del_range (hb_codepoint_t a, hb_codepoint_t b) 295 { 296 if (unlikely (!successful)) return; 297 if (unlikely (a > b || a == INVALID)) return; 298 dirty (); 299 unsigned int ma = get_major (a); 300 unsigned int mb = get_major (b); 301 /* Delete pages from ds through de if ds <= de. */ 302 int ds = (a == major_start (ma))? (int) ma: (int) (ma + 1); 303 int de = (b + 1 == major_start (mb + 1))? (int) mb: ((int) mb - 1); 304 if (ds > de || (int) ma < ds) 305 { 306 page_t *page = page_for (a); 307 if (page) 308 { 309 if (ma == mb) 310 page->del_range (a, b); 311 else 312 page->del_range (a, major_start (ma + 1) - 1); 313 } 314 } 315 if (de < (int) mb && ma != mb) 316 { 317 page_t *page = page_for (b); 318 if (page) 319 page->del_range (major_start (mb), b); 320 } 321 del_pages (ds, de); 322 } 323 gethb_bit_set_t324 bool get (hb_codepoint_t g) const 325 { 326 const page_t *page = page_for (g); 327 if (!page) 328 return false; 329 return page->get (g); 330 } 331 332 /* Has interface. */ operator []hb_bit_set_t333 bool operator [] (hb_codepoint_t k) const { return get (k); } hashb_bit_set_t334 bool has (hb_codepoint_t k) const { return (*this)[k]; } 335 /* Predicate. */ operator ()hb_bit_set_t336 bool operator () (hb_codepoint_t k) const { return has (k); } 337 338 /* Sink interface. */ operator <<hb_bit_set_t339 hb_bit_set_t& operator << (hb_codepoint_t v) 340 { add (v); return *this; } operator <<hb_bit_set_t341 hb_bit_set_t& operator << (const hb_pair_t<hb_codepoint_t, hb_codepoint_t>& range) 342 { add_range (range.first, range.second); return *this; } 343 intersectshb_bit_set_t344 bool intersects (hb_codepoint_t first, hb_codepoint_t last) const 345 { 346 hb_codepoint_t c = first - 1; 347 return next (&c) && c <= last; 348 } sethb_bit_set_t349 void set (const hb_bit_set_t &other) 350 { 351 if (unlikely (!successful)) return; 352 unsigned int count = other.pages.length; 353 if (unlikely (!resize (count, false))) 354 return; 355 population = other.population; 356 357 page_map = other.page_map; 358 pages = other.pages; 359 } 360 is_equalhb_bit_set_t361 bool is_equal (const hb_bit_set_t &other) const 362 { 363 if (has_population () && other.has_population () && 364 population != other.population) 365 return false; 366 367 unsigned int na = pages.length; 368 unsigned int nb = other.pages.length; 369 370 unsigned int a = 0, b = 0; 371 for (; a < na && b < nb; ) 372 { 373 if (page_at (a).is_empty ()) { a++; continue; } 374 if (other.page_at (b).is_empty ()) { b++; continue; } 375 if (page_map[a].major != other.page_map[b].major || 376 !page_at (a).is_equal (other.page_at (b))) 377 return false; 378 a++; 379 b++; 380 } 381 for (; a < na; a++) 382 if (!page_at (a).is_empty ()) { return false; } 383 for (; b < nb; b++) 384 if (!other.page_at (b).is_empty ()) { return false; } 385 386 return true; 387 } 388 is_subsethb_bit_set_t389 bool is_subset (const hb_bit_set_t &larger_set) const 390 { 391 if (has_population () && larger_set.has_population () && 392 population > larger_set.population) 393 return false; 394 395 uint32_t spi = 0; 396 for (uint32_t lpi = 0; spi < page_map.length && lpi < larger_set.page_map.length; lpi++) 397 { 398 uint32_t spm = page_map[spi].major; 399 uint32_t lpm = larger_set.page_map[lpi].major; 400 auto sp = page_at (spi); 401 auto lp = larger_set.page_at (lpi); 402 403 if (spm < lpm && !sp.is_empty ()) 404 return false; 405 406 if (lpm < spm) 407 continue; 408 409 if (!sp.is_subset (lp)) 410 return false; 411 412 spi++; 413 } 414 415 while (spi < page_map.length) 416 if (!page_at (spi++).is_empty ()) 417 return false; 418 419 return true; 420 } 421 422 private: allocate_compact_workspacehb_bit_set_t423 bool allocate_compact_workspace (hb_vector_t<unsigned>& workspace) 424 { 425 if (unlikely (!workspace.resize (pages.length))) 426 { 427 successful = false; 428 return false; 429 } 430 431 return true; 432 } 433 434 /* 435 * workspace should be a pre-sized vector allocated to hold at exactly pages.length 436 * elements. 437 */ compacthb_bit_set_t438 void compact (hb_vector_t<unsigned>& workspace, 439 unsigned int length) 440 { 441 assert(workspace.length == pages.length); 442 hb_vector_t<unsigned>& old_index_to_page_map_index = workspace; 443 444 hb_fill (old_index_to_page_map_index.writer(), 0xFFFFFFFF); 445 for (unsigned i = 0; i < length; i++) 446 old_index_to_page_map_index[page_map[i].index] = i; 447 448 compact_pages (old_index_to_page_map_index); 449 } compact_pageshb_bit_set_t450 void compact_pages (const hb_vector_t<unsigned>& old_index_to_page_map_index) 451 { 452 unsigned int write_index = 0; 453 for (unsigned int i = 0; i < pages.length; i++) 454 { 455 if (old_index_to_page_map_index[i] == 0xFFFFFFFF) continue; 456 457 if (write_index < i) 458 pages[write_index] = pages[i]; 459 460 page_map[old_index_to_page_map_index[i]].index = write_index; 461 write_index++; 462 } 463 } 464 public: 465 process_hb_bit_set_t466 void process_ (hb_bit_page_t::vector_t (*op) (const hb_bit_page_t::vector_t &, const hb_bit_page_t::vector_t &), 467 bool passthru_left, bool passthru_right, 468 const hb_bit_set_t &other) 469 { 470 if (unlikely (!successful)) return; 471 472 dirty (); 473 474 unsigned int na = pages.length; 475 unsigned int nb = other.pages.length; 476 unsigned int next_page = na; 477 478 unsigned int count = 0, newCount = 0; 479 unsigned int a = 0, b = 0; 480 unsigned int write_index = 0; 481 482 // Pre-allocate the workspace that compact() will need so we can bail on allocation failure 483 // before attempting to rewrite the page map. 484 hb_vector_t<unsigned> compact_workspace; 485 if (!passthru_left && unlikely (!allocate_compact_workspace (compact_workspace))) return; 486 487 for (; a < na && b < nb; ) 488 { 489 if (page_map[a].major == other.page_map[b].major) 490 { 491 if (!passthru_left) 492 { 493 // Move page_map entries that we're keeping from the left side set 494 // to the front of the page_map vector. This isn't necessary if 495 // passthru_left is set since no left side pages will be removed 496 // in that case. 497 if (write_index < a) 498 page_map[write_index] = page_map[a]; 499 write_index++; 500 } 501 502 count++; 503 a++; 504 b++; 505 } 506 else if (page_map[a].major < other.page_map[b].major) 507 { 508 if (passthru_left) 509 count++; 510 a++; 511 } 512 else 513 { 514 if (passthru_right) 515 count++; 516 b++; 517 } 518 } 519 if (passthru_left) 520 count += na - a; 521 if (passthru_right) 522 count += nb - b; 523 524 if (!passthru_left) 525 { 526 na = write_index; 527 next_page = write_index; 528 compact (compact_workspace, write_index); 529 } 530 531 if (unlikely (!resize (count))) 532 return; 533 534 newCount = count; 535 536 /* Process in-place backward. */ 537 a = na; 538 b = nb; 539 for (; a && b; ) 540 { 541 if (page_map.arrayZ[a - 1].major == other.page_map.arrayZ[b - 1].major) 542 { 543 a--; 544 b--; 545 count--; 546 page_map.arrayZ[count] = page_map.arrayZ[a]; 547 page_at (count).v = op (page_at (a).v, other.page_at (b).v); 548 } 549 else if (page_map.arrayZ[a - 1].major > other.page_map.arrayZ[b - 1].major) 550 { 551 a--; 552 if (passthru_left) 553 { 554 count--; 555 page_map.arrayZ[count] = page_map.arrayZ[a]; 556 } 557 } 558 else 559 { 560 b--; 561 if (passthru_right) 562 { 563 count--; 564 page_map.arrayZ[count].major = other.page_map.arrayZ[b].major; 565 page_map.arrayZ[count].index = next_page++; 566 page_at (count).v = other.page_at (b).v; 567 } 568 } 569 } 570 if (passthru_left) 571 while (a) 572 { 573 a--; 574 count--; 575 page_map.arrayZ[count] = page_map.arrayZ[a]; 576 } 577 if (passthru_right) 578 while (b) 579 { 580 b--; 581 count--; 582 page_map.arrayZ[count].major = other.page_map.arrayZ[b].major; 583 page_map.arrayZ[count].index = next_page++; 584 page_at (count).v = other.page_at (b).v; 585 } 586 assert (!count); 587 resize (newCount); 588 } 589 template <typename Op> 590 static hb_bit_page_t::vector_t op_hb_bit_set_t591 op_ (const hb_bit_page_t::vector_t &a, const hb_bit_page_t::vector_t &b) 592 { return Op{} (a, b); } 593 template <typename Op> processhb_bit_set_t594 void process (const Op& op, const hb_bit_set_t &other) 595 { 596 process_ (op_<Op>, op (1, 0), op (0, 1), other); 597 } 598 union_hb_bit_set_t599 void union_ (const hb_bit_set_t &other) { process (hb_bitwise_or, other); } intersecthb_bit_set_t600 void intersect (const hb_bit_set_t &other) { process (hb_bitwise_and, other); } subtracthb_bit_set_t601 void subtract (const hb_bit_set_t &other) { process (hb_bitwise_gt, other); } symmetric_differencehb_bit_set_t602 void symmetric_difference (const hb_bit_set_t &other) { process (hb_bitwise_xor, other); } 603 nexthb_bit_set_t604 bool next (hb_codepoint_t *codepoint) const 605 { 606 if (unlikely (*codepoint == INVALID)) { 607 *codepoint = get_min (); 608 return *codepoint != INVALID; 609 } 610 611 const auto* page_map_array = page_map.arrayZ; 612 unsigned int major = get_major (*codepoint); 613 unsigned int i = last_page_lookup; 614 615 if (unlikely (i >= page_map.length || page_map_array[i].major != major)) 616 { 617 page_map.bfind (major, &i, HB_NOT_FOUND_STORE_CLOSEST); 618 if (i >= page_map.length) { 619 *codepoint = INVALID; 620 return false; 621 } 622 } 623 624 const auto* pages_array = pages.arrayZ; 625 const page_map_t ¤t = page_map_array[i]; 626 if (likely (current.major == major)) 627 { 628 if (pages_array[current.index].next (codepoint)) 629 { 630 *codepoint += current.major * page_t::PAGE_BITS; 631 last_page_lookup = i; 632 return true; 633 } 634 i++; 635 } 636 637 for (; i < page_map.length; i++) 638 { 639 const page_map_t ¤t = page_map_array[i]; 640 hb_codepoint_t m = pages_array[current.index].get_min (); 641 if (m != INVALID) 642 { 643 *codepoint = current.major * page_t::PAGE_BITS + m; 644 last_page_lookup = i; 645 return true; 646 } 647 } 648 last_page_lookup = 0; 649 *codepoint = INVALID; 650 return false; 651 } previoushb_bit_set_t652 bool previous (hb_codepoint_t *codepoint) const 653 { 654 if (unlikely (*codepoint == INVALID)) { 655 *codepoint = get_max (); 656 return *codepoint != INVALID; 657 } 658 659 page_map_t map = {get_major (*codepoint), 0}; 660 unsigned int i; 661 page_map.bfind (map, &i, HB_NOT_FOUND_STORE_CLOSEST); 662 if (i < page_map.length && page_map.arrayZ[i].major == map.major) 663 { 664 if (pages[page_map.arrayZ[i].index].previous (codepoint)) 665 { 666 *codepoint += page_map.arrayZ[i].major * page_t::PAGE_BITS; 667 return true; 668 } 669 } 670 i--; 671 for (; (int) i >= 0; i--) 672 { 673 hb_codepoint_t m = pages.arrayZ[page_map.arrayZ[i].index].get_max (); 674 if (m != INVALID) 675 { 676 *codepoint = page_map.arrayZ[i].major * page_t::PAGE_BITS + m; 677 return true; 678 } 679 } 680 *codepoint = INVALID; 681 return false; 682 } next_rangehb_bit_set_t683 bool next_range (hb_codepoint_t *first, hb_codepoint_t *last) const 684 { 685 hb_codepoint_t i; 686 687 i = *last; 688 if (!next (&i)) 689 { 690 *last = *first = INVALID; 691 return false; 692 } 693 694 /* TODO Speed up. */ 695 *last = *first = i; 696 while (next (&i) && i == *last + 1) 697 (*last)++; 698 699 return true; 700 } previous_rangehb_bit_set_t701 bool previous_range (hb_codepoint_t *first, hb_codepoint_t *last) const 702 { 703 hb_codepoint_t i; 704 705 i = *first; 706 if (!previous (&i)) 707 { 708 *last = *first = INVALID; 709 return false; 710 } 711 712 /* TODO Speed up. */ 713 *last = *first = i; 714 while (previous (&i) && i == *first - 1) 715 (*first)--; 716 717 return true; 718 } 719 next_manyhb_bit_set_t720 unsigned int next_many (hb_codepoint_t codepoint, 721 hb_codepoint_t *out, 722 unsigned int size) const 723 { 724 // By default, start at the first bit of the first page of values. 725 unsigned int start_page = 0; 726 unsigned int start_page_value = 0; 727 if (unlikely (codepoint != INVALID)) 728 { 729 const auto* page_map_array = page_map.arrayZ; 730 unsigned int major = get_major (codepoint); 731 unsigned int i = last_page_lookup; 732 if (unlikely (i >= page_map.length || page_map_array[i].major != major)) 733 { 734 page_map.bfind (major, &i, HB_NOT_FOUND_STORE_CLOSEST); 735 if (i >= page_map.length) 736 return 0; // codepoint is greater than our max element. 737 } 738 start_page = i; 739 start_page_value = page_remainder (codepoint + 1); 740 if (unlikely (start_page_value == 0)) 741 { 742 // The export-after value was last in the page. Start on next page. 743 start_page++; 744 start_page_value = 0; 745 } 746 } 747 748 unsigned int initial_size = size; 749 for (unsigned int i = start_page; i < page_map.length && size; i++) 750 { 751 uint32_t base = major_start (page_map[i].major); 752 unsigned int n = pages[page_map[i].index].write (base, start_page_value, out, size); 753 out += n; 754 size -= n; 755 start_page_value = 0; 756 } 757 return initial_size - size; 758 } 759 next_many_invertedhb_bit_set_t760 unsigned int next_many_inverted (hb_codepoint_t codepoint, 761 hb_codepoint_t *out, 762 unsigned int size) const 763 { 764 unsigned int initial_size = size; 765 // By default, start at the first bit of the first page of values. 766 unsigned int start_page = 0; 767 unsigned int start_page_value = 0; 768 if (unlikely (codepoint != INVALID)) 769 { 770 const auto* page_map_array = page_map.arrayZ; 771 unsigned int major = get_major (codepoint); 772 unsigned int i = last_page_lookup; 773 if (unlikely (i >= page_map.length || page_map_array[i].major != major)) 774 { 775 page_map.bfind(major, &i, HB_NOT_FOUND_STORE_CLOSEST); 776 if (unlikely (i >= page_map.length)) 777 { 778 // codepoint is greater than our max element. 779 while (++codepoint != INVALID && size) 780 { 781 *out++ = codepoint; 782 size--; 783 } 784 return initial_size - size; 785 } 786 } 787 start_page = i; 788 start_page_value = page_remainder (codepoint + 1); 789 if (unlikely (start_page_value == 0)) 790 { 791 // The export-after value was last in the page. Start on next page. 792 start_page++; 793 start_page_value = 0; 794 } 795 } 796 797 hb_codepoint_t next_value = codepoint + 1; 798 for (unsigned int i=start_page; i<page_map.length && size; i++) 799 { 800 uint32_t base = major_start (page_map[i].major); 801 unsigned int n = pages[page_map[i].index].write_inverted (base, start_page_value, out, size, &next_value); 802 out += n; 803 size -= n; 804 start_page_value = 0; 805 } 806 while (next_value < HB_SET_VALUE_INVALID && size) { 807 *out++ = next_value++; 808 size--; 809 } 810 return initial_size - size; 811 } 812 has_populationhb_bit_set_t813 bool has_population () const { return population != UINT_MAX; } get_populationhb_bit_set_t814 unsigned int get_population () const 815 { 816 if (has_population ()) 817 return population; 818 819 unsigned int pop = 0; 820 unsigned int count = pages.length; 821 for (unsigned int i = 0; i < count; i++) 822 pop += pages[i].get_population (); 823 824 population = pop; 825 return pop; 826 } get_minhb_bit_set_t827 hb_codepoint_t get_min () const 828 { 829 unsigned count = pages.length; 830 for (unsigned i = 0; i < count; i++) 831 { 832 const auto& map = page_map[i]; 833 const auto& page = pages[map.index]; 834 835 if (!page.is_empty ()) 836 return map.major * page_t::PAGE_BITS + page.get_min (); 837 } 838 return INVALID; 839 } get_maxhb_bit_set_t840 hb_codepoint_t get_max () const 841 { 842 unsigned count = pages.length; 843 for (signed i = count - 1; i >= 0; i--) 844 { 845 const auto& map = page_map[(unsigned) i]; 846 const auto& page = pages[map.index]; 847 848 if (!page.is_empty ()) 849 return map.major * page_t::PAGE_BITS + page.get_max (); 850 } 851 return INVALID; 852 } 853 854 static constexpr hb_codepoint_t INVALID = page_t::INVALID; 855 856 /* 857 * Iterator implementation. 858 */ 859 struct iter_t : hb_iter_with_fallback_t<iter_t, hb_codepoint_t> 860 { 861 static constexpr bool is_sorted_iterator = true; iter_thb_bit_set_t::iter_t862 iter_t (const hb_bit_set_t &s_ = Null (hb_bit_set_t), 863 bool init = true) : s (&s_), v (INVALID), l(0) 864 { 865 if (init) 866 { 867 l = s->get_population () + 1; 868 __next__ (); 869 } 870 } 871 872 typedef hb_codepoint_t __item_t__; __item__hb_bit_set_t::iter_t873 hb_codepoint_t __item__ () const { return v; } __more__hb_bit_set_t::iter_t874 bool __more__ () const { return v != INVALID; } __next__hb_bit_set_t::iter_t875 void __next__ () { s->next (&v); if (l) l--; } __prev__hb_bit_set_t::iter_t876 void __prev__ () { s->previous (&v); } __len__hb_bit_set_t::iter_t877 unsigned __len__ () const { return l; } endhb_bit_set_t::iter_t878 iter_t end () const { return iter_t (*s, false); } operator !=hb_bit_set_t::iter_t879 bool operator != (const iter_t& o) const 880 { return s != o.s || v != o.v; } 881 882 protected: 883 const hb_bit_set_t *s; 884 hb_codepoint_t v; 885 unsigned l; 886 }; iterhb_bit_set_t887 iter_t iter () const { return iter_t (*this); } operator iter_thb_bit_set_t888 operator iter_t () const { return iter (); } 889 890 protected: 891 page_forhb_bit_set_t892 page_t *page_for (hb_codepoint_t g, bool insert = false) 893 { 894 unsigned major = get_major (g); 895 896 /* The extra page_map length is necessary; can't just rely on vector here, 897 * since the next check would be tricked because a null page also has 898 * major==0, which we can't distinguish from an actualy major==0 page... */ 899 unsigned i = last_page_lookup; 900 if (likely (i < page_map.length)) 901 { 902 auto &cached_page = page_map.arrayZ[i]; 903 if (cached_page.major == major) 904 return &pages.arrayZ[cached_page.index]; 905 } 906 907 page_map_t map = {major, pages.length}; 908 if (!page_map.bfind (map, &i, HB_NOT_FOUND_STORE_CLOSEST)) 909 { 910 if (!insert) 911 return nullptr; 912 913 if (unlikely (!resize (pages.length + 1))) 914 return nullptr; 915 916 pages.arrayZ[map.index].init0 (); 917 memmove (page_map.arrayZ + i + 1, 918 page_map.arrayZ + i, 919 (page_map.length - 1 - i) * page_map.item_size); 920 page_map[i] = map; 921 } 922 923 last_page_lookup = i; 924 return &pages.arrayZ[page_map.arrayZ[i].index]; 925 } page_forhb_bit_set_t926 const page_t *page_for (hb_codepoint_t g) const 927 { 928 unsigned major = get_major (g); 929 930 /* The extra page_map length is necessary; can't just rely on vector here, 931 * since the next check would be tricked because a null page also has 932 * major==0, which we can't distinguish from an actualy major==0 page... */ 933 unsigned i = last_page_lookup; 934 if (likely (i < page_map.length)) 935 { 936 auto &cached_page = page_map.arrayZ[i]; 937 if (cached_page.major == major) 938 return &pages.arrayZ[cached_page.index]; 939 } 940 941 page_map_t key = {major}; 942 if (!page_map.bfind (key, &i)) 943 return nullptr; 944 945 last_page_lookup = i; 946 return &pages.arrayZ[page_map[i].index]; 947 } page_athb_bit_set_t948 page_t &page_at (unsigned int i) 949 { 950 assert (i < page_map.length); 951 return pages.arrayZ[page_map.arrayZ[i].index]; 952 } page_athb_bit_set_t953 const page_t &page_at (unsigned int i) const 954 { 955 assert (i < page_map.length); 956 return pages.arrayZ[page_map.arrayZ[i].index]; 957 } get_majorhb_bit_set_t958 unsigned int get_major (hb_codepoint_t g) const { return g >> page_t::PAGE_BITS_LOG_2; } page_remainderhb_bit_set_t959 unsigned int page_remainder (hb_codepoint_t g) const { return g & page_t::PAGE_BITMASK; } major_starthb_bit_set_t960 hb_codepoint_t major_start (unsigned int major) const { return major << page_t::PAGE_BITS_LOG_2; } 961 }; 962 963 964 #endif /* HB_BIT_SET_HH */ 965