1 /* 2 * Copyright © 2018 Adobe Inc. 3 * 4 * This is part of HarfBuzz, a text shaping library. 5 * 6 * Permission is hereby granted, without written agreement and without 7 * license or royalty fees, to use, copy, modify, and distribute this 8 * software and its documentation for any purpose, provided that the 9 * above copyright notice and the following two paragraphs appear in 10 * all copies of this software. 11 * 12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 16 * DAMAGE. 17 * 18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 23 * 24 * Adobe Author(s): Michiharu Ariza 25 */ 26 27 #ifndef HB_SUBSET_CFF_COMMON_HH 28 #define HB_SUBSET_CFF_COMMON_HH 29 30 #include "hb.hh" 31 32 #include "hb-subset-plan.hh" 33 #include "hb-cff-interp-cs-common.hh" 34 35 namespace CFF { 36 37 /* Used for writing a temporary charstring */ 38 struct str_encoder_t 39 { str_encoder_tCFF::str_encoder_t40 str_encoder_t (str_buff_t &buff_) 41 : buff (buff_), error (false) {} 42 resetCFF::str_encoder_t43 void reset () { buff.resize (0); } 44 encode_byteCFF::str_encoder_t45 void encode_byte (unsigned char b) 46 { 47 if (unlikely (buff.push (b) == &Crap (unsigned char))) 48 set_error (); 49 } 50 encode_intCFF::str_encoder_t51 void encode_int (int v) 52 { 53 if ((-1131 <= v) && (v <= 1131)) 54 { 55 if ((-107 <= v) && (v <= 107)) 56 encode_byte (v + 139); 57 else if (v > 0) 58 { 59 v -= 108; 60 encode_byte ((v >> 8) + OpCode_TwoBytePosInt0); 61 encode_byte (v & 0xFF); 62 } 63 else 64 { 65 v = -v - 108; 66 encode_byte ((v >> 8) + OpCode_TwoByteNegInt0); 67 encode_byte (v & 0xFF); 68 } 69 } 70 else 71 { 72 if (unlikely (v < -32768)) 73 v = -32768; 74 else if (unlikely (v > 32767)) 75 v = 32767; 76 encode_byte (OpCode_shortint); 77 encode_byte ((v >> 8) & 0xFF); 78 encode_byte (v & 0xFF); 79 } 80 } 81 encode_numCFF::str_encoder_t82 void encode_num (const number_t& n) 83 { 84 if (n.in_int_range ()) 85 { 86 encode_int (n.to_int ()); 87 } 88 else 89 { 90 int32_t v = n.to_fixed (); 91 encode_byte (OpCode_fixedcs); 92 encode_byte ((v >> 24) & 0xFF); 93 encode_byte ((v >> 16) & 0xFF); 94 encode_byte ((v >> 8) & 0xFF); 95 encode_byte (v & 0xFF); 96 } 97 } 98 encode_opCFF::str_encoder_t99 void encode_op (op_code_t op) 100 { 101 if (Is_OpCode_ESC (op)) 102 { 103 encode_byte (OpCode_escape); 104 encode_byte (Unmake_OpCode_ESC (op)); 105 } 106 else 107 encode_byte (op); 108 } 109 copy_strCFF::str_encoder_t110 void copy_str (const byte_str_t &str) 111 { 112 unsigned int offset = buff.length; 113 if (unlikely (!buff.resize (offset + str.length))) 114 { 115 set_error (); 116 return; 117 } 118 if (unlikely (buff.length < offset + str.length)) 119 { 120 set_error (); 121 return; 122 } 123 memcpy (&buff[offset], &str[0], str.length); 124 } 125 is_errorCFF::str_encoder_t126 bool is_error () const { return error; } 127 128 protected: set_errorCFF::str_encoder_t129 void set_error () { error = true; } 130 131 str_buff_t &buff; 132 bool error; 133 }; 134 135 struct cff_sub_table_info_t { cff_sub_table_info_tCFF::cff_sub_table_info_t136 cff_sub_table_info_t () 137 : fd_array_link (0), 138 char_strings_link (0) 139 { 140 fd_select.init (); 141 } 142 143 table_info_t fd_select; 144 objidx_t fd_array_link; 145 objidx_t char_strings_link; 146 }; 147 148 template <typename OPSTR=op_str_t> 149 struct cff_top_dict_op_serializer_t : op_serializer_t 150 { serializeCFF::cff_top_dict_op_serializer_t151 bool serialize (hb_serialize_context_t *c, 152 const OPSTR &opstr, 153 const cff_sub_table_info_t &info) const 154 { 155 TRACE_SERIALIZE (this); 156 157 switch (opstr.op) 158 { 159 case OpCode_CharStrings: 160 return_trace (FontDict::serialize_link4_op(c, opstr.op, info.char_strings_link, whence_t::Absolute)); 161 162 case OpCode_FDArray: 163 return_trace (FontDict::serialize_link4_op(c, opstr.op, info.fd_array_link, whence_t::Absolute)); 164 165 case OpCode_FDSelect: 166 return_trace (FontDict::serialize_link4_op(c, opstr.op, info.fd_select.link, whence_t::Absolute)); 167 168 default: 169 return_trace (copy_opstr (c, opstr)); 170 } 171 return_trace (true); 172 } 173 }; 174 175 struct cff_font_dict_op_serializer_t : op_serializer_t 176 { serializeCFF::cff_font_dict_op_serializer_t177 bool serialize (hb_serialize_context_t *c, 178 const op_str_t &opstr, 179 const table_info_t &privateDictInfo) const 180 { 181 TRACE_SERIALIZE (this); 182 183 if (opstr.op == OpCode_Private) 184 { 185 /* serialize the private dict size & offset as 2-byte & 4-byte integers */ 186 return_trace (UnsizedByteStr::serialize_int2 (c, privateDictInfo.size) && 187 Dict::serialize_link4_op (c, opstr.op, privateDictInfo.link, whence_t::Absolute)); 188 } 189 else 190 { 191 HBUINT8 *d = c->allocate_size<HBUINT8> (opstr.str.length); 192 if (unlikely (!d)) return_trace (false); 193 memcpy (d, &opstr.str[0], opstr.str.length); 194 } 195 return_trace (true); 196 } 197 }; 198 199 struct cff_private_dict_op_serializer_t : op_serializer_t 200 { cff_private_dict_op_serializer_tCFF::cff_private_dict_op_serializer_t201 cff_private_dict_op_serializer_t (bool desubroutinize_, bool drop_hints_) 202 : desubroutinize (desubroutinize_), drop_hints (drop_hints_) {} 203 serializeCFF::cff_private_dict_op_serializer_t204 bool serialize (hb_serialize_context_t *c, 205 const op_str_t &opstr, 206 objidx_t subrs_link) const 207 { 208 TRACE_SERIALIZE (this); 209 210 if (drop_hints && dict_opset_t::is_hint_op (opstr.op)) 211 return true; 212 if (opstr.op == OpCode_Subrs) 213 { 214 if (desubroutinize || !subrs_link) 215 return_trace (true); 216 else 217 return_trace (FontDict::serialize_link2_op (c, opstr.op, subrs_link)); 218 } 219 else 220 return_trace (copy_opstr (c, opstr)); 221 } 222 223 protected: 224 const bool desubroutinize; 225 const bool drop_hints; 226 }; 227 228 struct flatten_param_t 229 { 230 str_buff_t &flatStr; 231 bool drop_hints; 232 }; 233 234 template <typename ACC, typename ENV, typename OPSET, op_code_t endchar_op=OpCode_Invalid> 235 struct subr_flattener_t 236 { subr_flattener_tCFF::subr_flattener_t237 subr_flattener_t (const ACC &acc_, 238 const hb_subset_plan_t *plan_) 239 : acc (acc_), plan (plan_) {} 240 flattenCFF::subr_flattener_t241 bool flatten (str_buff_vec_t &flat_charstrings) 242 { 243 if (!flat_charstrings.resize (plan->num_output_glyphs ())) 244 return false; 245 for (unsigned int i = 0; i < plan->num_output_glyphs (); i++) 246 flat_charstrings[i].init (); 247 for (unsigned int i = 0; i < plan->num_output_glyphs (); i++) 248 { 249 hb_codepoint_t glyph; 250 if (!plan->old_gid_for_new_gid (i, &glyph)) 251 { 252 /* add an endchar only charstring for a missing glyph if CFF1 */ 253 if (endchar_op != OpCode_Invalid) flat_charstrings[i].push (endchar_op); 254 continue; 255 } 256 const byte_str_t str = (*acc.charStrings)[glyph]; 257 unsigned int fd = acc.fdSelect->get_fd (glyph); 258 if (unlikely (fd >= acc.fdCount)) 259 return false; 260 cs_interpreter_t<ENV, OPSET, flatten_param_t> interp; 261 interp.env.init (str, acc, fd); 262 flatten_param_t param = { 263 flat_charstrings[i], 264 (bool) (plan->flags & HB_SUBSET_FLAGS_NO_HINTING) 265 }; 266 if (unlikely (!interp.interpret (param))) 267 return false; 268 } 269 return true; 270 } 271 272 const ACC &acc; 273 const hb_subset_plan_t *plan; 274 }; 275 276 struct subr_closures_t 277 { subr_closures_tCFF::subr_closures_t278 subr_closures_t (unsigned int fd_count) : valid (false), global_closure (), local_closures () 279 { 280 valid = true; 281 if (!local_closures.resize (fd_count)) 282 valid = false; 283 } 284 resetCFF::subr_closures_t285 void reset () 286 { 287 global_closure.clear(); 288 for (unsigned int i = 0; i < local_closures.length; i++) 289 local_closures[i].clear(); 290 } 291 is_validCFF::subr_closures_t292 bool is_valid () const { return valid; } 293 bool valid; 294 hb_set_t global_closure; 295 hb_vector_t<hb_set_t> local_closures; 296 }; 297 298 struct parsed_cs_op_t : op_str_t 299 { initCFF::parsed_cs_op_t300 void init (unsigned int subr_num_ = 0) 301 { 302 subr_num = subr_num_; 303 drop_flag = false; 304 keep_flag = false; 305 skip_flag = false; 306 } 307 for_dropCFF::parsed_cs_op_t308 bool for_drop () const { return drop_flag; } set_dropCFF::parsed_cs_op_t309 void set_drop () { if (!for_keep ()) drop_flag = true; } 310 for_keepCFF::parsed_cs_op_t311 bool for_keep () const { return keep_flag; } set_keepCFF::parsed_cs_op_t312 void set_keep () { keep_flag = true; } 313 for_skipCFF::parsed_cs_op_t314 bool for_skip () const { return skip_flag; } set_skipCFF::parsed_cs_op_t315 void set_skip () { skip_flag = true; } 316 317 unsigned int subr_num; 318 319 protected: 320 bool drop_flag : 1; 321 bool keep_flag : 1; 322 bool skip_flag : 1; 323 }; 324 325 struct parsed_cs_str_t : parsed_values_t<parsed_cs_op_t> 326 { initCFF::parsed_cs_str_t327 void init () 328 { 329 SUPER::init (); 330 parsed = false; 331 hint_dropped = false; 332 has_prefix_ = false; 333 } 334 add_opCFF::parsed_cs_str_t335 void add_op (op_code_t op, const byte_str_ref_t& str_ref) 336 { 337 if (!is_parsed ()) 338 SUPER::add_op (op, str_ref); 339 } 340 add_call_opCFF::parsed_cs_str_t341 void add_call_op (op_code_t op, const byte_str_ref_t& str_ref, unsigned int subr_num) 342 { 343 if (!is_parsed ()) 344 { 345 unsigned int parsed_len = get_count (); 346 if (likely (parsed_len > 0)) 347 values[parsed_len-1].set_skip (); 348 349 parsed_cs_op_t val; 350 val.init (subr_num); 351 SUPER::add_op (op, str_ref, val); 352 } 353 } 354 set_prefixCFF::parsed_cs_str_t355 void set_prefix (const number_t &num, op_code_t op = OpCode_Invalid) 356 { 357 has_prefix_ = true; 358 prefix_op_ = op; 359 prefix_num_ = num; 360 } 361 at_endCFF::parsed_cs_str_t362 bool at_end (unsigned int pos) const 363 { 364 return ((pos + 1 >= values.length) /* CFF2 */ 365 || (values[pos + 1].op == OpCode_return)); 366 } 367 is_parsedCFF::parsed_cs_str_t368 bool is_parsed () const { return parsed; } set_parsedCFF::parsed_cs_str_t369 void set_parsed () { parsed = true; } 370 is_hint_droppedCFF::parsed_cs_str_t371 bool is_hint_dropped () const { return hint_dropped; } set_hint_droppedCFF::parsed_cs_str_t372 void set_hint_dropped () { hint_dropped = true; } 373 is_vsindex_droppedCFF::parsed_cs_str_t374 bool is_vsindex_dropped () const { return vsindex_dropped; } set_vsindex_droppedCFF::parsed_cs_str_t375 void set_vsindex_dropped () { vsindex_dropped = true; } 376 has_prefixCFF::parsed_cs_str_t377 bool has_prefix () const { return has_prefix_; } prefix_opCFF::parsed_cs_str_t378 op_code_t prefix_op () const { return prefix_op_; } prefix_numCFF::parsed_cs_str_t379 const number_t &prefix_num () const { return prefix_num_; } 380 381 protected: 382 bool parsed; 383 bool hint_dropped; 384 bool vsindex_dropped; 385 bool has_prefix_; 386 op_code_t prefix_op_; 387 number_t prefix_num_; 388 389 private: 390 typedef parsed_values_t<parsed_cs_op_t> SUPER; 391 }; 392 393 struct parsed_cs_str_vec_t : hb_vector_t<parsed_cs_str_t> 394 { 395 private: 396 typedef hb_vector_t<parsed_cs_str_t> SUPER; 397 }; 398 399 struct subr_subset_param_t 400 { initCFF::subr_subset_param_t401 void init (parsed_cs_str_t *parsed_charstring_, 402 parsed_cs_str_vec_t *parsed_global_subrs_, parsed_cs_str_vec_t *parsed_local_subrs_, 403 hb_set_t *global_closure_, hb_set_t *local_closure_, 404 bool drop_hints_) 405 { 406 parsed_charstring = parsed_charstring_; 407 current_parsed_str = parsed_charstring; 408 parsed_global_subrs = parsed_global_subrs_; 409 parsed_local_subrs = parsed_local_subrs_; 410 global_closure = global_closure_; 411 local_closure = local_closure_; 412 drop_hints = drop_hints_; 413 } 414 get_parsed_str_for_contextCFF::subr_subset_param_t415 parsed_cs_str_t *get_parsed_str_for_context (call_context_t &context) 416 { 417 switch (context.type) 418 { 419 case CSType_CharString: 420 return parsed_charstring; 421 422 case CSType_LocalSubr: 423 if (likely (context.subr_num < parsed_local_subrs->length)) 424 return &(*parsed_local_subrs)[context.subr_num]; 425 break; 426 427 case CSType_GlobalSubr: 428 if (likely (context.subr_num < parsed_global_subrs->length)) 429 return &(*parsed_global_subrs)[context.subr_num]; 430 break; 431 } 432 return nullptr; 433 } 434 435 template <typename ENV> set_current_strCFF::subr_subset_param_t436 void set_current_str (ENV &env, bool calling) 437 { 438 parsed_cs_str_t *parsed_str = get_parsed_str_for_context (env.context); 439 if (unlikely (!parsed_str)) 440 { 441 env.set_error (); 442 return; 443 } 444 /* If the called subroutine is parsed partially but not completely yet, 445 * it must be because we are calling it recursively. 446 * Handle it as an error. */ 447 if (unlikely (calling && !parsed_str->is_parsed () && (parsed_str->values.length > 0))) 448 env.set_error (); 449 else 450 current_parsed_str = parsed_str; 451 } 452 453 parsed_cs_str_t *current_parsed_str; 454 455 parsed_cs_str_t *parsed_charstring; 456 parsed_cs_str_vec_t *parsed_global_subrs; 457 parsed_cs_str_vec_t *parsed_local_subrs; 458 hb_set_t *global_closure; 459 hb_set_t *local_closure; 460 bool drop_hints; 461 }; 462 463 struct subr_remap_t : hb_inc_bimap_t 464 { createCFF::subr_remap_t465 void create (const hb_set_t *closure) 466 { 467 /* create a remapping of subroutine numbers from old to new. 468 * no optimization based on usage counts. fonttools doesn't appear doing that either. 469 */ 470 471 hb_codepoint_t old_num = HB_SET_VALUE_INVALID; 472 while (hb_set_next (closure, &old_num)) 473 add (old_num); 474 475 if (get_population () < 1240) 476 bias = 107; 477 else if (get_population () < 33900) 478 bias = 1131; 479 else 480 bias = 32768; 481 } 482 biased_numCFF::subr_remap_t483 int biased_num (unsigned int old_num) const 484 { 485 hb_codepoint_t new_num = get (old_num); 486 return (int)new_num - bias; 487 } 488 489 protected: 490 int bias; 491 }; 492 493 struct subr_remaps_t 494 { subr_remaps_tCFF::subr_remaps_t495 subr_remaps_t (unsigned int fdCount) 496 { 497 local_remaps.resize (fdCount); 498 } 499 in_errorCFF::subr_remaps_t500 bool in_error() 501 { 502 return local_remaps.in_error (); 503 } 504 createCFF::subr_remaps_t505 void create (subr_closures_t& closures) 506 { 507 global_remap.create (&closures.global_closure); 508 for (unsigned int i = 0; i < local_remaps.length; i++) 509 local_remaps[i].create (&closures.local_closures[i]); 510 } 511 512 subr_remap_t global_remap; 513 hb_vector_t<subr_remap_t> local_remaps; 514 }; 515 516 template <typename SUBSETTER, typename SUBRS, typename ACC, typename ENV, typename OPSET, op_code_t endchar_op=OpCode_Invalid> 517 struct subr_subsetter_t 518 { subr_subsetter_tCFF::subr_subsetter_t519 subr_subsetter_t (ACC &acc_, const hb_subset_plan_t *plan_) 520 : acc (acc_), plan (plan_), closures(acc_.fdCount), remaps(acc_.fdCount) 521 {} 522 523 /* Subroutine subsetting with --no-desubroutinize runs in phases: 524 * 525 * 1. execute charstrings/subroutines to determine subroutine closures 526 * 2. parse out all operators and numbers 527 * 3. mark hint operators and operands for removal if --no-hinting 528 * 4. re-encode all charstrings and subroutines with new subroutine numbers 529 * 530 * Phases #1 and #2 are done at the same time in collect_subrs (). 531 * Phase #3 walks charstrings/subroutines forward then backward (hence parsing required), 532 * because we can't tell if a number belongs to a hint op until we see the first moveto. 533 * 534 * Assumption: a callsubr/callgsubr operator must immediately follow a (biased) subroutine number 535 * within the same charstring/subroutine, e.g., not split across a charstring and a subroutine. 536 */ subsetCFF::subr_subsetter_t537 bool subset (void) 538 { 539 parsed_charstrings.resize (plan->num_output_glyphs ()); 540 parsed_global_subrs.resize (acc.globalSubrs->count); 541 542 if (unlikely (remaps.in_error() 543 || parsed_charstrings.in_error () 544 || parsed_global_subrs.in_error ())) { 545 return false; 546 } 547 548 if (unlikely (!parsed_local_subrs.resize (acc.fdCount))) return false; 549 550 for (unsigned int i = 0; i < acc.fdCount; i++) 551 { 552 parsed_local_subrs[i].resize (acc.privateDicts[i].localSubrs->count); 553 if (unlikely (parsed_local_subrs[i].in_error ())) return false; 554 } 555 if (unlikely (!closures.valid)) 556 return false; 557 558 /* phase 1 & 2 */ 559 for (unsigned int i = 0; i < plan->num_output_glyphs (); i++) 560 { 561 hb_codepoint_t glyph; 562 if (!plan->old_gid_for_new_gid (i, &glyph)) 563 continue; 564 const byte_str_t str = (*acc.charStrings)[glyph]; 565 unsigned int fd = acc.fdSelect->get_fd (glyph); 566 if (unlikely (fd >= acc.fdCount)) 567 return false; 568 569 cs_interpreter_t<ENV, OPSET, subr_subset_param_t> interp; 570 interp.env.init (str, acc, fd); 571 572 subr_subset_param_t param; 573 param.init (&parsed_charstrings[i], 574 &parsed_global_subrs, &parsed_local_subrs[fd], 575 &closures.global_closure, &closures.local_closures[fd], 576 plan->flags & HB_SUBSET_FLAGS_NO_HINTING); 577 578 if (unlikely (!interp.interpret (param))) 579 return false; 580 581 /* complete parsed string esp. copy CFF1 width or CFF2 vsindex to the parsed charstring for encoding */ 582 SUBSETTER::complete_parsed_str (interp.env, param, parsed_charstrings[i]); 583 } 584 585 if (plan->flags & HB_SUBSET_FLAGS_NO_HINTING) 586 { 587 /* mark hint ops and arguments for drop */ 588 for (unsigned int i = 0; i < plan->num_output_glyphs (); i++) 589 { 590 hb_codepoint_t glyph; 591 if (!plan->old_gid_for_new_gid (i, &glyph)) 592 continue; 593 unsigned int fd = acc.fdSelect->get_fd (glyph); 594 if (unlikely (fd >= acc.fdCount)) 595 return false; 596 subr_subset_param_t param; 597 param.init (&parsed_charstrings[i], 598 &parsed_global_subrs, &parsed_local_subrs[fd], 599 &closures.global_closure, &closures.local_closures[fd], 600 plan->flags & HB_SUBSET_FLAGS_NO_HINTING); 601 602 drop_hints_param_t drop; 603 if (drop_hints_in_str (parsed_charstrings[i], param, drop)) 604 { 605 parsed_charstrings[i].set_hint_dropped (); 606 if (drop.vsindex_dropped) 607 parsed_charstrings[i].set_vsindex_dropped (); 608 } 609 } 610 611 /* after dropping hints recreate closures of actually used subrs */ 612 closures.reset (); 613 for (unsigned int i = 0; i < plan->num_output_glyphs (); i++) 614 { 615 hb_codepoint_t glyph; 616 if (!plan->old_gid_for_new_gid (i, &glyph)) 617 continue; 618 unsigned int fd = acc.fdSelect->get_fd (glyph); 619 if (unlikely (fd >= acc.fdCount)) 620 return false; 621 subr_subset_param_t param; 622 param.init (&parsed_charstrings[i], 623 &parsed_global_subrs, &parsed_local_subrs[fd], 624 &closures.global_closure, &closures.local_closures[fd], 625 plan->flags & HB_SUBSET_FLAGS_NO_HINTING); 626 collect_subr_refs_in_str (parsed_charstrings[i], param); 627 } 628 } 629 630 remaps.create (closures); 631 632 return true; 633 } 634 encode_charstringsCFF::subr_subsetter_t635 bool encode_charstrings (str_buff_vec_t &buffArray) const 636 { 637 if (unlikely (!buffArray.resize (plan->num_output_glyphs ()))) 638 return false; 639 for (unsigned int i = 0; i < plan->num_output_glyphs (); i++) 640 { 641 hb_codepoint_t glyph; 642 if (!plan->old_gid_for_new_gid (i, &glyph)) 643 { 644 /* add an endchar only charstring for a missing glyph if CFF1 */ 645 if (endchar_op != OpCode_Invalid) buffArray[i].push (endchar_op); 646 continue; 647 } 648 unsigned int fd = acc.fdSelect->get_fd (glyph); 649 if (unlikely (fd >= acc.fdCount)) 650 return false; 651 if (unlikely (!encode_str (parsed_charstrings[i], fd, buffArray[i]))) 652 return false; 653 } 654 return true; 655 } 656 encode_subrsCFF::subr_subsetter_t657 bool encode_subrs (const parsed_cs_str_vec_t &subrs, const subr_remap_t& remap, unsigned int fd, str_buff_vec_t &buffArray) const 658 { 659 unsigned int count = remap.get_population (); 660 661 if (unlikely (!buffArray.resize (count))) 662 return false; 663 for (unsigned int old_num = 0; old_num < subrs.length; old_num++) 664 { 665 hb_codepoint_t new_num = remap[old_num]; 666 if (new_num != CFF_UNDEF_CODE) 667 { 668 if (unlikely (!encode_str (subrs[old_num], fd, buffArray[new_num]))) 669 return false; 670 } 671 } 672 return true; 673 } 674 encode_globalsubrsCFF::subr_subsetter_t675 bool encode_globalsubrs (str_buff_vec_t &buffArray) 676 { 677 return encode_subrs (parsed_global_subrs, remaps.global_remap, 0, buffArray); 678 } 679 encode_localsubrsCFF::subr_subsetter_t680 bool encode_localsubrs (unsigned int fd, str_buff_vec_t &buffArray) const 681 { 682 return encode_subrs (parsed_local_subrs[fd], remaps.local_remaps[fd], fd, buffArray); 683 } 684 685 protected: 686 struct drop_hints_param_t 687 { drop_hints_param_tCFF::subr_subsetter_t::drop_hints_param_t688 drop_hints_param_t () 689 : seen_moveto (false), 690 ends_in_hint (false), 691 all_dropped (false), 692 vsindex_dropped (false) {} 693 694 bool seen_moveto; 695 bool ends_in_hint; 696 bool all_dropped; 697 bool vsindex_dropped; 698 }; 699 drop_hints_in_subrCFF::subr_subsetter_t700 bool drop_hints_in_subr (parsed_cs_str_t &str, unsigned int pos, 701 parsed_cs_str_vec_t &subrs, unsigned int subr_num, 702 const subr_subset_param_t ¶m, drop_hints_param_t &drop) 703 { 704 drop.ends_in_hint = false; 705 bool has_hint = drop_hints_in_str (subrs[subr_num], param, drop); 706 707 /* if this subr ends with a stem hint (i.e., not a number; potential argument for moveto), 708 * then this entire subroutine must be a hint. drop its call. */ 709 if (drop.ends_in_hint) 710 { 711 str.values[pos].set_drop (); 712 /* if this subr call is at the end of the parent subr, propagate the flag 713 * otherwise reset the flag */ 714 if (!str.at_end (pos)) 715 drop.ends_in_hint = false; 716 } 717 else if (drop.all_dropped) 718 { 719 str.values[pos].set_drop (); 720 } 721 722 return has_hint; 723 } 724 725 /* returns true if it sees a hint op before the first moveto */ drop_hints_in_strCFF::subr_subsetter_t726 bool drop_hints_in_str (parsed_cs_str_t &str, const subr_subset_param_t ¶m, drop_hints_param_t &drop) 727 { 728 bool seen_hint = false; 729 730 for (unsigned int pos = 0; pos < str.values.length; pos++) 731 { 732 bool has_hint = false; 733 switch (str.values[pos].op) 734 { 735 case OpCode_callsubr: 736 has_hint = drop_hints_in_subr (str, pos, 737 *param.parsed_local_subrs, str.values[pos].subr_num, 738 param, drop); 739 break; 740 741 case OpCode_callgsubr: 742 has_hint = drop_hints_in_subr (str, pos, 743 *param.parsed_global_subrs, str.values[pos].subr_num, 744 param, drop); 745 break; 746 747 case OpCode_rmoveto: 748 case OpCode_hmoveto: 749 case OpCode_vmoveto: 750 drop.seen_moveto = true; 751 break; 752 753 case OpCode_hintmask: 754 case OpCode_cntrmask: 755 if (drop.seen_moveto) 756 { 757 str.values[pos].set_drop (); 758 break; 759 } 760 HB_FALLTHROUGH; 761 762 case OpCode_hstemhm: 763 case OpCode_vstemhm: 764 case OpCode_hstem: 765 case OpCode_vstem: 766 has_hint = true; 767 str.values[pos].set_drop (); 768 if (str.at_end (pos)) 769 drop.ends_in_hint = true; 770 break; 771 772 case OpCode_dotsection: 773 str.values[pos].set_drop (); 774 break; 775 776 default: 777 /* NONE */ 778 break; 779 } 780 if (has_hint) 781 { 782 for (int i = pos - 1; i >= 0; i--) 783 { 784 parsed_cs_op_t &csop = str.values[(unsigned)i]; 785 if (csop.for_drop ()) 786 break; 787 csop.set_drop (); 788 if (csop.op == OpCode_vsindexcs) 789 drop.vsindex_dropped = true; 790 } 791 seen_hint |= has_hint; 792 } 793 } 794 795 /* Raise all_dropped flag if all operators except return are dropped from a subr. 796 * It may happen even after seeing the first moveto if a subr contains 797 * only (usually one) hintmask operator, then calls to this subr can be dropped. 798 */ 799 drop.all_dropped = true; 800 for (unsigned int pos = 0; pos < str.values.length; pos++) 801 { 802 parsed_cs_op_t &csop = str.values[pos]; 803 if (csop.op == OpCode_return) 804 break; 805 if (!csop.for_drop ()) 806 { 807 drop.all_dropped = false; 808 break; 809 } 810 } 811 812 return seen_hint; 813 } 814 collect_subr_refs_in_subrCFF::subr_subsetter_t815 void collect_subr_refs_in_subr (parsed_cs_str_t &str, unsigned int pos, 816 unsigned int subr_num, parsed_cs_str_vec_t &subrs, 817 hb_set_t *closure, 818 const subr_subset_param_t ¶m) 819 { 820 closure->add (subr_num); 821 collect_subr_refs_in_str (subrs[subr_num], param); 822 } 823 collect_subr_refs_in_strCFF::subr_subsetter_t824 void collect_subr_refs_in_str (parsed_cs_str_t &str, const subr_subset_param_t ¶m) 825 { 826 for (unsigned int pos = 0; pos < str.values.length; pos++) 827 { 828 if (!str.values[pos].for_drop ()) 829 { 830 switch (str.values[pos].op) 831 { 832 case OpCode_callsubr: 833 collect_subr_refs_in_subr (str, pos, 834 str.values[pos].subr_num, *param.parsed_local_subrs, 835 param.local_closure, param); 836 break; 837 838 case OpCode_callgsubr: 839 collect_subr_refs_in_subr (str, pos, 840 str.values[pos].subr_num, *param.parsed_global_subrs, 841 param.global_closure, param); 842 break; 843 844 default: break; 845 } 846 } 847 } 848 } 849 encode_strCFF::subr_subsetter_t850 bool encode_str (const parsed_cs_str_t &str, const unsigned int fd, str_buff_t &buff) const 851 { 852 buff.init (); 853 str_encoder_t encoder (buff); 854 encoder.reset (); 855 /* if a prefix (CFF1 width or CFF2 vsindex) has been removed along with hints, 856 * re-insert it at the beginning of charstreing */ 857 if (str.has_prefix () && str.is_hint_dropped ()) 858 { 859 encoder.encode_num (str.prefix_num ()); 860 if (str.prefix_op () != OpCode_Invalid) 861 encoder.encode_op (str.prefix_op ()); 862 } 863 for (unsigned int i = 0; i < str.get_count(); i++) 864 { 865 const parsed_cs_op_t &opstr = str.values[i]; 866 if (!opstr.for_drop () && !opstr.for_skip ()) 867 { 868 switch (opstr.op) 869 { 870 case OpCode_callsubr: 871 encoder.encode_int (remaps.local_remaps[fd].biased_num (opstr.subr_num)); 872 encoder.encode_op (OpCode_callsubr); 873 break; 874 875 case OpCode_callgsubr: 876 encoder.encode_int (remaps.global_remap.biased_num (opstr.subr_num)); 877 encoder.encode_op (OpCode_callgsubr); 878 break; 879 880 default: 881 encoder.copy_str (opstr.str); 882 break; 883 } 884 } 885 } 886 return !encoder.is_error (); 887 } 888 889 protected: 890 const ACC &acc; 891 const hb_subset_plan_t *plan; 892 893 subr_closures_t closures; 894 895 parsed_cs_str_vec_t parsed_charstrings; 896 parsed_cs_str_vec_t parsed_global_subrs; 897 hb_vector_t<parsed_cs_str_vec_t> parsed_local_subrs; 898 899 subr_remaps_t remaps; 900 901 private: 902 typedef typename SUBRS::count_type subr_count_type; 903 }; 904 905 } /* namespace CFF */ 906 907 HB_INTERNAL bool 908 hb_plan_subset_cff_fdselect (const hb_subset_plan_t *plan, 909 unsigned int fdCount, 910 const CFF::FDSelect &src, /* IN */ 911 unsigned int &subset_fd_count /* OUT */, 912 unsigned int &subset_fdselect_size /* OUT */, 913 unsigned int &subset_fdselect_format /* OUT */, 914 hb_vector_t<CFF::code_pair_t> &fdselect_ranges /* OUT */, 915 hb_inc_bimap_t &fdmap /* OUT */); 916 917 HB_INTERNAL bool 918 hb_serialize_cff_fdselect (hb_serialize_context_t *c, 919 unsigned int num_glyphs, 920 const CFF::FDSelect &src, 921 unsigned int fd_count, 922 unsigned int fdselect_format, 923 unsigned int size, 924 const hb_vector_t<CFF::code_pair_t> &fdselect_ranges); 925 926 #endif /* HB_SUBSET_CFF_COMMON_HH */ 927