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 {
40 str_encoder_t (str_buff_t &buff_)
41 : buff (buff_), error (false) {}
42
43 void reset () { buff.resize (0); }
44
45 void encode_byte (unsigned char b)
46 {
47 if (unlikely (buff.push (b) == &Crap(unsigned char)))
48 set_error ();
49 }
50
51 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
82 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
99 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
110 void copy_str (const byte_str_t &str)
111 {
112 unsigned int offset = buff.length;
113 buff.resize (offset + str.length);
114 if (unlikely (buff.length < offset + str.length))
115 {
116 set_error ();
117 return;
118 }
119 memcpy (&buff[offset], &str[0], str.length);
120 }
121
122 bool is_error () const { return error; }
123
124 protected:
125 void set_error () { error = true; }
126
127 str_buff_t &buff;
128 bool error;
129 };
130
131 struct cff_sub_table_offsets_t {
132 cff_sub_table_offsets_t () : privateDictsOffset (0)
133 {
134 topDictInfo.init ();
135 FDSelectInfo.init ();
136 FDArrayInfo.init ();
137 charStringsInfo.init ();
138 globalSubrsInfo.init ();
139 localSubrsInfos.init ();
140 }
141
142 ~cff_sub_table_offsets_t () { localSubrsInfos.fini (); }
143
144 table_info_t topDictInfo;
145 table_info_t FDSelectInfo;
146 table_info_t FDArrayInfo;
147 table_info_t charStringsInfo;
148 unsigned int privateDictsOffset;
149 table_info_t globalSubrsInfo;
150 hb_vector_t<table_info_t> localSubrsInfos;
151 };
152
153 template <typename OPSTR=op_str_t>
154 struct cff_top_dict_op_serializer_t : op_serializer_t
155 {
156 bool serialize (hb_serialize_context_t *c,
157 const OPSTR &opstr,
158 const cff_sub_table_offsets_t &offsets) const
159 {
160 TRACE_SERIALIZE (this);
161
162 switch (opstr.op)
163 {
164 case OpCode_CharStrings:
165 return_trace (FontDict::serialize_offset4_op(c, opstr.op, offsets.charStringsInfo.offset));
166
167 case OpCode_FDArray:
168 return_trace (FontDict::serialize_offset4_op(c, opstr.op, offsets.FDArrayInfo.offset));
169
170 case OpCode_FDSelect:
171 return_trace (FontDict::serialize_offset4_op(c, opstr.op, offsets.FDSelectInfo.offset));
172
173 default:
174 return_trace (copy_opstr (c, opstr));
175 }
176 return_trace (true);
177 }
178
179 unsigned int calculate_serialized_size (const OPSTR &opstr) const
180 {
181 switch (opstr.op)
182 {
183 case OpCode_CharStrings:
184 case OpCode_FDArray:
185 case OpCode_FDSelect:
186 return OpCode_Size (OpCode_longintdict) + 4 + OpCode_Size (opstr.op);
187
188 default:
189 return opstr.str.length;
190 }
191 }
192 };
193
194 struct cff_font_dict_op_serializer_t : op_serializer_t
195 {
196 bool serialize (hb_serialize_context_t *c,
197 const op_str_t &opstr,
198 const table_info_t &privateDictInfo) const
199 {
200 TRACE_SERIALIZE (this);
201
202 if (opstr.op == OpCode_Private)
203 {
204 /* serialize the private dict size & offset as 2-byte & 4-byte integers */
205 if (unlikely (!UnsizedByteStr::serialize_int2 (c, privateDictInfo.size) ||
206 !UnsizedByteStr::serialize_int4 (c, privateDictInfo.offset)))
207 return_trace (false);
208
209 /* serialize the opcode */
210 HBUINT8 *p = c->allocate_size<HBUINT8> (1);
211 if (unlikely (p == nullptr)) return_trace (false);
212 p->set (OpCode_Private);
213
214 return_trace (true);
215 }
216 else
217 {
218 HBUINT8 *d = c->allocate_size<HBUINT8> (opstr.str.length);
219 if (unlikely (d == nullptr)) return_trace (false);
220 memcpy (d, &opstr.str[0], opstr.str.length);
221 }
222 return_trace (true);
223 }
224
225 unsigned int calculate_serialized_size (const op_str_t &opstr) const
226 {
227 if (opstr.op == OpCode_Private)
228 return OpCode_Size (OpCode_longintdict) + 4 + OpCode_Size (OpCode_shortint) + 2 + OpCode_Size (OpCode_Private);
229 else
230 return opstr.str.length;
231 }
232 };
233
234 struct cff_private_dict_op_serializer_t : op_serializer_t
235 {
236 cff_private_dict_op_serializer_t (bool desubroutinize_, bool drop_hints_)
237 : desubroutinize (desubroutinize_), drop_hints (drop_hints_) {}
238
239 bool serialize (hb_serialize_context_t *c,
240 const op_str_t &opstr,
241 const unsigned int subrsOffset) const
242 {
243 TRACE_SERIALIZE (this);
244
245 if (drop_hints && dict_opset_t::is_hint_op (opstr.op))
246 return true;
247 if (opstr.op == OpCode_Subrs)
248 {
249 if (desubroutinize || (subrsOffset == 0))
250 return_trace (true);
251 else
252 return_trace (FontDict::serialize_offset2_op (c, opstr.op, subrsOffset));
253 }
254 else
255 return_trace (copy_opstr (c, opstr));
256 }
257
258 unsigned int calculate_serialized_size (const op_str_t &opstr,
259 bool has_localsubr=true) const
260 {
261 if (drop_hints && dict_opset_t::is_hint_op (opstr.op))
262 return 0;
263 if (opstr.op == OpCode_Subrs)
264 {
265 if (desubroutinize || !has_localsubr)
266 return 0;
267 else
268 return OpCode_Size (OpCode_shortint) + 2 + OpCode_Size (opstr.op);
269 }
270 else
271 return opstr.str.length;
272 }
273
274 protected:
275 const bool desubroutinize;
276 const bool drop_hints;
277 };
278
279 struct flatten_param_t
280 {
281 str_buff_t &flatStr;
282 bool drop_hints;
283 };
284
285 template <typename ACC, typename ENV, typename OPSET>
286 struct subr_flattener_t
287 {
288 subr_flattener_t (const ACC &acc_,
289 const hb_vector_t<hb_codepoint_t> &glyphs_,
290 bool drop_hints_) : acc (acc_), glyphs (glyphs_),
291 drop_hints (drop_hints_) {}
292
293 bool flatten (str_buff_vec_t &flat_charstrings)
294 {
295 if (!flat_charstrings.resize (glyphs.length))
296 return false;
297 for (unsigned int i = 0; i < glyphs.length; i++)
298 flat_charstrings[i].init ();
299 for (unsigned int i = 0; i < glyphs.length; i++)
300 {
301 hb_codepoint_t glyph = glyphs[i];
302 const byte_str_t str = (*acc.charStrings)[glyph];
303 unsigned int fd = acc.fdSelect->get_fd (glyph);
304 if (unlikely (fd >= acc.fdCount))
305 return false;
306 cs_interpreter_t<ENV, OPSET, flatten_param_t> interp;
307 interp.env.init (str, acc, fd);
308 flatten_param_t param = { flat_charstrings[i], drop_hints };
309 if (unlikely (!interp.interpret (param)))
310 return false;
311 }
312 return true;
313 }
314
315 const ACC &acc;
316 const hb_vector_t<hb_codepoint_t> &glyphs;
317 bool drop_hints;
318 };
319
320 struct subr_closures_t
321 {
322 subr_closures_t () : valid (false), global_closure (nullptr)
323 { local_closures.init (); }
324
325 void init (unsigned int fd_count)
326 {
327 valid = true;
328 global_closure = hb_set_create ();
329 if (global_closure == hb_set_get_empty ())
330 valid = false;
331 if (!local_closures.resize (fd_count))
332 valid = false;
333
334 for (unsigned int i = 0; i < local_closures.length; i++)
335 {
336 local_closures[i] = hb_set_create ();
337 if (local_closures[i] == hb_set_get_empty ())
338 valid = false;
339 }
340 }
341
342 void fini ()
343 {
344 hb_set_destroy (global_closure);
345 for (unsigned int i = 0; i < local_closures.length; i++)
346 hb_set_destroy (local_closures[i]);
347 local_closures.fini ();
348 }
349
350 void reset ()
351 {
352 hb_set_clear (global_closure);
353 for (unsigned int i = 0; i < local_closures.length; i++)
354 hb_set_clear (local_closures[i]);
355 }
356
357 bool is_valid () const { return valid; }
358 bool valid;
359 hb_set_t *global_closure;
360 hb_vector_t<hb_set_t *> local_closures;
361 };
362
363 struct parsed_cs_op_t : op_str_t
364 {
365 void init (unsigned int subr_num_ = 0)
366 {
367 op_str_t::init ();
368 subr_num = subr_num_;
369 drop_flag = false;
370 keep_flag = false;
371 skip_flag = false;
372 }
373
374 void fini () { op_str_t::fini (); }
375
376 bool for_drop () const { return drop_flag; }
377 void set_drop () { if (!for_keep ()) drop_flag = true; }
378
379 bool for_keep () const { return keep_flag; }
380 void set_keep () { keep_flag = true; }
381
382 bool for_skip () const { return skip_flag; }
383 void set_skip () { skip_flag = true; }
384
385 unsigned int subr_num;
386
387 protected:
388 bool drop_flag : 1;
389 bool keep_flag : 1;
390 bool skip_flag : 1;
391 };
392
393 struct parsed_cs_str_t : parsed_values_t<parsed_cs_op_t>
394 {
395 void init ()
396 {
397 SUPER::init ();
398 parsed = false;
399 hint_dropped = false;
400 has_prefix_ = false;
401 }
402
403 void add_op (op_code_t op, const byte_str_ref_t& str_ref)
404 {
405 if (!is_parsed ())
406 SUPER::add_op (op, str_ref);
407 }
408
409 void add_call_op (op_code_t op, const byte_str_ref_t& str_ref, unsigned int subr_num)
410 {
411 if (!is_parsed ())
412 {
413 unsigned int parsed_len = get_count ();
414 if (likely (parsed_len > 0))
415 values[parsed_len-1].set_skip ();
416
417 parsed_cs_op_t val;
418 val.init (subr_num);
419 SUPER::add_op (op, str_ref, val);
420 }
421 }
422
423 void set_prefix (const number_t &num, op_code_t op = OpCode_Invalid)
424 {
425 has_prefix_ = true;
426 prefix_op_ = op;
427 prefix_num_ = num;
428 }
429
430 bool at_end (unsigned int pos) const
431 {
432 return ((pos + 1 >= values.length) /* CFF2 */
433 || (values[pos + 1].op == OpCode_return));
434 }
435
436 bool is_parsed () const { return parsed; }
437 void set_parsed () { parsed = true; }
438
439 bool is_hint_dropped () const { return hint_dropped; }
440 void set_hint_dropped () { hint_dropped = true; }
441
442 bool is_vsindex_dropped () const { return vsindex_dropped; }
443 void set_vsindex_dropped () { vsindex_dropped = true; }
444
445 bool has_prefix () const { return has_prefix_; }
446 op_code_t prefix_op () const { return prefix_op_; }
447 const number_t &prefix_num () const { return prefix_num_; }
448
449 protected:
450 bool parsed;
451 bool hint_dropped;
452 bool vsindex_dropped;
453 bool has_prefix_;
454 op_code_t prefix_op_;
455 number_t prefix_num_;
456
457 private:
458 typedef parsed_values_t<parsed_cs_op_t> SUPER;
459 };
460
461 struct parsed_cs_str_vec_t : hb_vector_t<parsed_cs_str_t>
462 {
463 void init (unsigned int len_ = 0)
464 {
465 SUPER::init ();
466 resize (len_);
467 for (unsigned int i = 0; i < length; i++)
468 (*this)[i].init ();
469 }
470 void fini () { SUPER::fini_deep (); }
471
472 private:
473 typedef hb_vector_t<parsed_cs_str_t> SUPER;
474 };
475
476 struct subr_subset_param_t
477 {
478 void init (parsed_cs_str_t *parsed_charstring_,
479 parsed_cs_str_vec_t *parsed_global_subrs_, parsed_cs_str_vec_t *parsed_local_subrs_,
480 hb_set_t *global_closure_, hb_set_t *local_closure_,
481 bool drop_hints_)
482 {
483 parsed_charstring = parsed_charstring_;
484 current_parsed_str = parsed_charstring;
485 parsed_global_subrs = parsed_global_subrs_;
486 parsed_local_subrs = parsed_local_subrs_;
487 global_closure = global_closure_;
488 local_closure = local_closure_;
489 drop_hints = drop_hints_;
490 }
491
492 parsed_cs_str_t *get_parsed_str_for_context (call_context_t &context)
493 {
494 switch (context.type)
495 {
496 case CSType_CharString:
497 return parsed_charstring;
498
499 case CSType_LocalSubr:
500 if (likely (context.subr_num < parsed_local_subrs->length))
501 return &(*parsed_local_subrs)[context.subr_num];
502 break;
503
504 case CSType_GlobalSubr:
505 if (likely (context.subr_num < parsed_global_subrs->length))
506 return &(*parsed_global_subrs)[context.subr_num];
507 break;
508 }
509 return nullptr;
510 }
511
512 template <typename ENV>
513 void set_current_str (ENV &env, bool calling)
514 {
515 parsed_cs_str_t *parsed_str = get_parsed_str_for_context (env.context);
516 if (likely (parsed_str != nullptr))
517 {
518 /* If the called subroutine is parsed partially but not completely yet,
519 * it must be because we are calling it recursively.
520 * Handle it as an error. */
521 if (unlikely (calling && !parsed_str->is_parsed () && (parsed_str->values.length > 0)))
522 env.set_error ();
523 else
524 current_parsed_str = parsed_str;
525 }
526 else
527 env.set_error ();
528 }
529
530 parsed_cs_str_t *current_parsed_str;
531
532 parsed_cs_str_t *parsed_charstring;
533 parsed_cs_str_vec_t *parsed_global_subrs;
534 parsed_cs_str_vec_t *parsed_local_subrs;
535 hb_set_t *global_closure;
536 hb_set_t *local_closure;
537 bool drop_hints;
538 };
539
540 struct subr_remap_t : remap_t
541 {
542 void create (hb_set_t *closure)
543 {
544 /* create a remapping of subroutine numbers from old to new.
545 * no optimization based on usage counts. fonttools doesn't appear doing that either.
546 */
547 reset (closure->get_max () + 1);
548 for (hb_codepoint_t old_num = 0; old_num < length; old_num++)
549 {
550 if (hb_set_has (closure, old_num))
551 add (old_num);
552 }
553
554 if (get_count () < 1240)
555 bias = 107;
556 else if (get_count () < 33900)
557 bias = 1131;
558 else
559 bias = 32768;
560 }
561
562 hb_codepoint_t operator[] (unsigned int old_num) const
563 {
564 if (old_num >= length)
565 return CFF_UNDEF_CODE;
566 else
567 return remap_t::operator[] (old_num);
568 }
569
570 int biased_num (unsigned int old_num) const
571 {
572 hb_codepoint_t new_num = (*this)[old_num];
573 return (int)new_num - bias;
574 }
575
576 protected:
577 int bias;
578 };
579
580 struct subr_remap_ts
581 {
582 subr_remap_ts ()
583 {
584 global_remap.init ();
585 local_remaps.init ();
586 }
587
588 ~subr_remap_ts () { fini (); }
589
590 void init (unsigned int fdCount)
591 {
592 local_remaps.resize (fdCount);
593 for (unsigned int i = 0; i < fdCount; i++)
594 local_remaps[i].init ();
595 }
596
597 void create (subr_closures_t& closures)
598 {
599 global_remap.create (closures.global_closure);
600 for (unsigned int i = 0; i < local_remaps.length; i++)
601 local_remaps[i].create (closures.local_closures[i]);
602 }
603
604 void fini ()
605 {
606 global_remap.fini ();
607 local_remaps.fini_deep ();
608 }
609
610 subr_remap_t global_remap;
611 hb_vector_t<subr_remap_t> local_remaps;
612 };
613
614 template <typename SUBSETTER, typename SUBRS, typename ACC, typename ENV, typename OPSET>
615 struct subr_subsetter_t
616 {
617 subr_subsetter_t ()
618 {
619 parsed_charstrings.init ();
620 parsed_global_subrs.init ();
621 parsed_local_subrs.init ();
622 }
623
624 ~subr_subsetter_t ()
625 {
626 closures.fini ();
627 remaps.fini ();
628 parsed_charstrings.fini_deep ();
629 parsed_global_subrs.fini_deep ();
630 parsed_local_subrs.fini_deep ();
631 }
632
633 /* Subroutine subsetting with --no-desubroutinize runs in phases:
634 *
635 * 1. execute charstrings/subroutines to determine subroutine closures
636 * 2. parse out all operators and numbers
637 * 3. mark hint operators and operands for removal if --no-hinting
638 * 4. re-encode all charstrings and subroutines with new subroutine numbers
639 *
640 * Phases #1 and #2 are done at the same time in collect_subrs ().
641 * Phase #3 walks charstrings/subroutines forward then backward (hence parsing required),
642 * because we can't tell if a number belongs to a hint op until we see the first moveto.
643 *
644 * Assumption: a callsubr/callgsubr operator must immediately follow a (biased) subroutine number
645 * within the same charstring/subroutine, e.g., not split across a charstring and a subroutine.
646 */
647 bool subset (ACC &acc, const hb_vector_t<hb_codepoint_t> &glyphs, bool drop_hints)
648 {
649 closures.init (acc.fdCount);
650 remaps.init (acc.fdCount);
651
652 parsed_charstrings.init (glyphs.length);
653 parsed_global_subrs.init (acc.globalSubrs->count);
654 parsed_local_subrs.resize (acc.fdCount);
655 for (unsigned int i = 0; i < acc.fdCount; i++)
656 {
657 parsed_local_subrs[i].init (acc.privateDicts[i].localSubrs->count);
658 }
659 if (unlikely (!closures.valid))
660 return false;
661
662 /* phase 1 & 2 */
663 for (unsigned int i = 0; i < glyphs.length; i++)
664 {
665 hb_codepoint_t glyph = glyphs[i];
666 const byte_str_t str = (*acc.charStrings)[glyph];
667 unsigned int fd = acc.fdSelect->get_fd (glyph);
668 if (unlikely (fd >= acc.fdCount))
669 return false;
670
671 cs_interpreter_t<ENV, OPSET, subr_subset_param_t> interp;
672 interp.env.init (str, acc, fd);
673
674 subr_subset_param_t param;
675 param.init (&parsed_charstrings[i],
676 &parsed_global_subrs, &parsed_local_subrs[fd],
677 closures.global_closure, closures.local_closures[fd],
678 drop_hints);
679
680 if (unlikely (!interp.interpret (param)))
681 return false;
682
683 /* finalize parsed string esp. copy CFF1 width or CFF2 vsindex to the parsed charstring for encoding */
684 SUBSETTER::finalize_parsed_str (interp.env, param, parsed_charstrings[i]);
685 }
686
687 if (drop_hints)
688 {
689 /* mark hint ops and arguments for drop */
690 for (unsigned int i = 0; i < glyphs.length; i++)
691 {
692 unsigned int fd = acc.fdSelect->get_fd (glyphs[i]);
693 if (unlikely (fd >= acc.fdCount))
694 return false;
695 subr_subset_param_t param;
696 param.init (&parsed_charstrings[i],
697 &parsed_global_subrs, &parsed_local_subrs[fd],
698 closures.global_closure, closures.local_closures[fd],
699 drop_hints);
700
701 drop_hints_param_t drop;
702 if (drop_hints_in_str (parsed_charstrings[i], param, drop))
703 {
704 parsed_charstrings[i].set_hint_dropped ();
705 if (drop.vsindex_dropped)
706 parsed_charstrings[i].set_vsindex_dropped ();
707 }
708 }
709
710 /* after dropping hints recreate closures of actually used subrs */
711 closures.reset ();
712 for (unsigned int i = 0; i < glyphs.length; i++)
713 {
714 unsigned int fd = acc.fdSelect->get_fd (glyphs[i]);
715 if (unlikely (fd >= acc.fdCount))
716 return false;
717 subr_subset_param_t param;
718 param.init (&parsed_charstrings[i],
719 &parsed_global_subrs, &parsed_local_subrs[fd],
720 closures.global_closure, closures.local_closures[fd],
721 drop_hints);
722 collect_subr_refs_in_str (parsed_charstrings[i], param);
723 }
724 }
725
726 remaps.create (closures);
727
728 return true;
729 }
730
731 bool encode_charstrings (ACC &acc, const hb_vector_t<hb_codepoint_t> &glyphs, str_buff_vec_t &buffArray) const
732 {
733 if (unlikely (!buffArray.resize (glyphs.length)))
734 return false;
735 for (unsigned int i = 0; i < glyphs.length; i++)
736 {
737 unsigned int fd = acc.fdSelect->get_fd (glyphs[i]);
738 if (unlikely (fd >= acc.fdCount))
739 return false;
740 if (unlikely (!encode_str (parsed_charstrings[i], fd, buffArray[i])))
741 return false;
742 }
743 return true;
744 }
745
746 bool encode_subrs (const parsed_cs_str_vec_t &subrs, const subr_remap_t& remap, unsigned int fd, str_buff_vec_t &buffArray) const
747 {
748 unsigned int count = remap.get_count ();
749
750 if (unlikely (!buffArray.resize (count)))
751 return false;
752 for (unsigned int old_num = 0; old_num < subrs.length; old_num++)
753 {
754 hb_codepoint_t new_num = remap[old_num];
755 if (new_num != CFF_UNDEF_CODE)
756 {
757 if (unlikely (!encode_str (subrs[old_num], fd, buffArray[new_num])))
758 return false;
759 }
760 }
761 return true;
762 }
763
764 bool encode_globalsubrs (str_buff_vec_t &buffArray)
765 {
766 return encode_subrs (parsed_global_subrs, remaps.global_remap, 0, buffArray);
767 }
768
769 bool encode_localsubrs (unsigned int fd, str_buff_vec_t &buffArray) const
770 {
771 return encode_subrs (parsed_local_subrs[fd], remaps.local_remaps[fd], fd, buffArray);
772 }
773
774 protected:
775 struct drop_hints_param_t
776 {
777 drop_hints_param_t ()
778 : seen_moveto (false),
779 ends_in_hint (false),
780 vsindex_dropped (false) {}
781
782 bool seen_moveto;
783 bool ends_in_hint;
784 bool vsindex_dropped;
785 };
786
787 bool drop_hints_in_subr (parsed_cs_str_t &str, unsigned int pos,
788 parsed_cs_str_vec_t &subrs, unsigned int subr_num,
789 const subr_subset_param_t ¶m, drop_hints_param_t &drop)
790 {
791 drop.ends_in_hint = false;
792 bool has_hint = drop_hints_in_str (subrs[subr_num], param, drop);
793
794 /* if this subr ends with a stem hint (i.e., not a number a potential argument for moveto),
795 * then this entire subroutine must be a hint. drop its call. */
796 if (drop.ends_in_hint)
797 {
798 str.values[pos].set_drop ();
799 /* if this subr call is at the end of the parent subr, propagate the flag
800 * otherwise reset the flag */
801 if (!str.at_end (pos))
802 drop.ends_in_hint = false;
803 }
804
805 return has_hint;
806 }
807
808 /* returns true if it sees a hint op before the first moveto */
809 bool drop_hints_in_str (parsed_cs_str_t &str, const subr_subset_param_t ¶m, drop_hints_param_t &drop)
810 {
811 bool seen_hint = false;
812
813 for (unsigned int pos = 0; pos < str.values.length; pos++)
814 {
815 bool has_hint = false;
816 switch (str.values[pos].op)
817 {
818 case OpCode_callsubr:
819 has_hint = drop_hints_in_subr (str, pos,
820 *param.parsed_local_subrs, str.values[pos].subr_num,
821 param, drop);
822
823 break;
824
825 case OpCode_callgsubr:
826 has_hint = drop_hints_in_subr (str, pos,
827 *param.parsed_global_subrs, str.values[pos].subr_num,
828 param, drop);
829 break;
830
831 case OpCode_rmoveto:
832 case OpCode_hmoveto:
833 case OpCode_vmoveto:
834 drop.seen_moveto = true;
835 break;
836
837 case OpCode_hintmask:
838 case OpCode_cntrmask:
839 if (drop.seen_moveto)
840 {
841 str.values[pos].set_drop ();
842 break;
843 }
844 HB_FALLTHROUGH;
845
846 case OpCode_hstemhm:
847 case OpCode_vstemhm:
848 case OpCode_hstem:
849 case OpCode_vstem:
850 has_hint = true;
851 str.values[pos].set_drop ();
852 if (str.at_end (pos))
853 drop.ends_in_hint = true;
854 break;
855
856 case OpCode_dotsection:
857 str.values[pos].set_drop ();
858 break;
859
860 default:
861 /* NONE */
862 break;
863 }
864 if (has_hint)
865 {
866 for (int i = pos - 1; i >= 0; i--)
867 {
868 parsed_cs_op_t &csop = str.values[(unsigned)i];
869 if (csop.for_drop ())
870 break;
871 csop.set_drop ();
872 if (csop.op == OpCode_vsindexcs)
873 drop.vsindex_dropped = true;
874 }
875 seen_hint |= has_hint;
876 }
877 }
878
879 return seen_hint;
880 }
881
882 void collect_subr_refs_in_subr (parsed_cs_str_t &str, unsigned int pos,
883 unsigned int subr_num, parsed_cs_str_vec_t &subrs,
884 hb_set_t *closure,
885 const subr_subset_param_t ¶m)
886 {
887 hb_set_add (closure, subr_num);
888 collect_subr_refs_in_str (subrs[subr_num], param);
889 }
890
891 void collect_subr_refs_in_str (parsed_cs_str_t &str, const subr_subset_param_t ¶m)
892 {
893 for (unsigned int pos = 0; pos < str.values.length; pos++)
894 {
895 if (!str.values[pos].for_drop ())
896 {
897 switch (str.values[pos].op)
898 {
899 case OpCode_callsubr:
900 collect_subr_refs_in_subr (str, pos,
901 str.values[pos].subr_num, *param.parsed_local_subrs,
902 param.local_closure, param);
903 break;
904
905 case OpCode_callgsubr:
906 collect_subr_refs_in_subr (str, pos,
907 str.values[pos].subr_num, *param.parsed_global_subrs,
908 param.global_closure, param);
909 break;
910
911 default: break;
912 }
913 }
914 }
915 }
916
917 bool encode_str (const parsed_cs_str_t &str, const unsigned int fd, str_buff_t &buff) const
918 {
919 buff.init ();
920 str_encoder_t encoder (buff);
921 encoder.reset ();
922 /* if a prefix (CFF1 width or CFF2 vsindex) has been removed along with hints,
923 * re-insert it at the beginning of charstreing */
924 if (str.has_prefix () && str.is_hint_dropped ())
925 {
926 encoder.encode_num (str.prefix_num ());
927 if (str.prefix_op () != OpCode_Invalid)
928 encoder.encode_op (str.prefix_op ());
929 }
930 for (unsigned int i = 0; i < str.get_count(); i++)
931 {
932 const parsed_cs_op_t &opstr = str.values[i];
933 if (!opstr.for_drop () && !opstr.for_skip ())
934 {
935 switch (opstr.op)
936 {
937 case OpCode_callsubr:
938 encoder.encode_int (remaps.local_remaps[fd].biased_num (opstr.subr_num));
939 encoder.encode_op (OpCode_callsubr);
940 break;
941
942 case OpCode_callgsubr:
943 encoder.encode_int (remaps.global_remap.biased_num (opstr.subr_num));
944 encoder.encode_op (OpCode_callgsubr);
945 break;
946
947 default:
948 encoder.copy_str (opstr.str);
949 break;
950 }
951 }
952 }
953 return !encoder.is_error ();
954 }
955
956 protected:
957 subr_closures_t closures;
958
959 parsed_cs_str_vec_t parsed_charstrings;
960 parsed_cs_str_vec_t parsed_global_subrs;
961 hb_vector_t<parsed_cs_str_vec_t> parsed_local_subrs;
962
963 subr_remap_ts remaps;
964
965 private:
966 typedef typename SUBRS::count_type subr_count_type;
967 };
968
969 } /* namespace CFF */
970
971 HB_INTERNAL bool
972 hb_plan_subset_cff_fdselect (const hb_vector_t<hb_codepoint_t> &glyphs,
973 unsigned int fdCount,
974 const CFF::FDSelect &src, /* IN */
975 unsigned int &subset_fd_count /* OUT */,
976 unsigned int &subset_fdselect_size /* OUT */,
977 unsigned int &subset_fdselect_format /* OUT */,
978 hb_vector_t<CFF::code_pair_t> &fdselect_ranges /* OUT */,
979 CFF::remap_t &fdmap /* OUT */);
980
981 HB_INTERNAL bool
982 hb_serialize_cff_fdselect (hb_serialize_context_t *c,
983 unsigned int num_glyphs,
984 const CFF::FDSelect &src,
985 unsigned int fd_count,
986 unsigned int fdselect_format,
987 unsigned int size,
988 const hb_vector_t<CFF::code_pair_t> &fdselect_ranges);
989
990 #endif /* HB_SUBSET_CFF_COMMON_HH */