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#ifndef HB_CFF_INTERP_COMMON_HH
27#define HB_CFF_INTERP_COMMON_HH
28
29namespace CFF {
30
31using namespace OT;
32
33typedef unsigned int op_code_t;
34
35
36/* === Dict operators === */
37
38/* One byte operators (0-31) */
39#define OpCode_version 0 /* CFF Top */
40#define OpCode_Notice 1 /* CFF Top */
41#define OpCode_FullName 2 /* CFF Top */
42#define OpCode_FamilyName 3 /* CFF Top */
43#define OpCode_Weight 4 /* CFF Top */
44#define OpCode_FontBBox 5 /* CFF Top */
45#define OpCode_BlueValues 6 /* CFF Private, CFF2 Private */
46#define OpCode_OtherBlues 7 /* CFF Private, CFF2 Private */
47#define OpCode_FamilyBlues 8 /* CFF Private, CFF2 Private */
48#define OpCode_FamilyOtherBlues 9 /* CFF Private, CFF2 Private */
49#define OpCode_StdHW 10 /* CFF Private, CFF2 Private */
50#define OpCode_StdVW 11 /* CFF Private, CFF2 Private */
51#define OpCode_escape 12 /* All. Shared with CS */
52#define OpCode_UniqueID 13 /* CFF Top */
53#define OpCode_XUID 14 /* CFF Top */
54#define OpCode_charset 15 /* CFF Top (0) */
55#define OpCode_Encoding 16 /* CFF Top (0) */
56#define OpCode_CharStrings 17 /* CFF Top, CFF2 Top */
57#define OpCode_Private 18 /* CFF Top, CFF2 FD */
58#define OpCode_Subrs 19 /* CFF Private, CFF2 Private */
59#define OpCode_defaultWidthX 20 /* CFF Private (0) */
60#define OpCode_nominalWidthX 21 /* CFF Private (0) */
61#define OpCode_vsindexdict 22 /* CFF2 Private/CS */
62#define OpCode_blenddict 23 /* CFF2 Private/CS */
63#define OpCode_vstore 24 /* CFF2 Top */
64#define OpCode_reserved25 25
65#define OpCode_reserved26 26
66#define OpCode_reserved27 27
67
68/* Numbers */
69#define OpCode_shortint 28 /* 16-bit integer, All */
70#define OpCode_longintdict 29 /* 32-bit integer, All */
71#define OpCode_BCD 30 /* Real number, CFF2 Top/FD */
72#define OpCode_reserved31 31
73
74/* 1-byte integers */
75#define OpCode_OneByteIntFirst 32 /* All. beginning of the range of first byte ints */
76#define OpCode_OneByteIntLast 246 /* All. ending of the range of first byte int */
77
78/* 2-byte integers */
79#define OpCode_TwoBytePosInt0 247 /* All. first byte of two byte positive int (+108 to +1131) */
80#define OpCode_TwoBytePosInt1 248
81#define OpCode_TwoBytePosInt2 249
82#define OpCode_TwoBytePosInt3 250
83
84#define OpCode_TwoByteNegInt0 251 /* All. first byte of two byte negative int (-1131 to -108) */
85#define OpCode_TwoByteNegInt1 252
86#define OpCode_TwoByteNegInt2 253
87#define OpCode_TwoByteNegInt3 254
88
89/* Two byte escape operators 12, (0-41) */
90#define OpCode_ESC_Base 256
91#define Make_OpCode_ESC(byte2) ((op_code_t)(OpCode_ESC_Base + (byte2)))
92
93inline op_code_t Unmake_OpCode_ESC (op_code_t op) { return (op_code_t)(op - OpCode_ESC_Base); }
94inline bool Is_OpCode_ESC (op_code_t op) { return op >= OpCode_ESC_Base; }
95inline unsigned int OpCode_Size (op_code_t op) { return Is_OpCode_ESC (op) ? 2: 1; }
96
97#define OpCode_Copyright Make_OpCode_ESC(0) /* CFF Top */
98#define OpCode_isFixedPitch Make_OpCode_ESC(1) /* CFF Top (false) */
99#define OpCode_ItalicAngle Make_OpCode_ESC(2) /* CFF Top (0) */
100#define OpCode_UnderlinePosition Make_OpCode_ESC(3) /* CFF Top (-100) */
101#define OpCode_UnderlineThickness Make_OpCode_ESC(4) /* CFF Top (50) */
102#define OpCode_PaintType Make_OpCode_ESC(5) /* CFF Top (0) */
103#define OpCode_CharstringType Make_OpCode_ESC(6) /* CFF Top (2) */
104#define OpCode_FontMatrix Make_OpCode_ESC(7) /* CFF Top, CFF2 Top (.001 0 0 .001 0 0)*/
105#define OpCode_StrokeWidth Make_OpCode_ESC(8) /* CFF Top (0) */
106#define OpCode_BlueScale Make_OpCode_ESC(9) /* CFF Private, CFF2 Private (0.039625) */
107#define OpCode_BlueShift Make_OpCode_ESC(10) /* CFF Private, CFF2 Private (7) */
108#define OpCode_BlueFuzz Make_OpCode_ESC(11) /* CFF Private, CFF2 Private (1) */
109#define OpCode_StemSnapH Make_OpCode_ESC(12) /* CFF Private, CFF2 Private */
110#define OpCode_StemSnapV Make_OpCode_ESC(13) /* CFF Private, CFF2 Private */
111#define OpCode_ForceBold Make_OpCode_ESC(14) /* CFF Private (false) */
112#define OpCode_reservedESC15 Make_OpCode_ESC(15)
113#define OpCode_reservedESC16 Make_OpCode_ESC(16)
114#define OpCode_LanguageGroup Make_OpCode_ESC(17) /* CFF Private, CFF2 Private (0) */
115#define OpCode_ExpansionFactor Make_OpCode_ESC(18) /* CFF Private, CFF2 Private (0.06) */
116#define OpCode_initialRandomSeed Make_OpCode_ESC(19) /* CFF Private (0) */
117#define OpCode_SyntheticBase Make_OpCode_ESC(20) /* CFF Top */
118#define OpCode_PostScript Make_OpCode_ESC(21) /* CFF Top */
119#define OpCode_BaseFontName Make_OpCode_ESC(22) /* CFF Top */
120#define OpCode_BaseFontBlend Make_OpCode_ESC(23) /* CFF Top */
121#define OpCode_reservedESC24 Make_OpCode_ESC(24)
122#define OpCode_reservedESC25 Make_OpCode_ESC(25)
123#define OpCode_reservedESC26 Make_OpCode_ESC(26)
124#define OpCode_reservedESC27 Make_OpCode_ESC(27)
125#define OpCode_reservedESC28 Make_OpCode_ESC(28)
126#define OpCode_reservedESC29 Make_OpCode_ESC(29)
127#define OpCode_ROS Make_OpCode_ESC(30) /* CFF Top_CID */
128#define OpCode_CIDFontVersion Make_OpCode_ESC(31) /* CFF Top_CID (0) */
129#define OpCode_CIDFontRevision Make_OpCode_ESC(32) /* CFF Top_CID (0) */
130#define OpCode_CIDFontType Make_OpCode_ESC(33) /* CFF Top_CID (0) */
131#define OpCode_CIDCount Make_OpCode_ESC(34) /* CFF Top_CID (8720) */
132#define OpCode_UIDBase Make_OpCode_ESC(35) /* CFF Top_CID */
133#define OpCode_FDArray Make_OpCode_ESC(36) /* CFF Top_CID, CFF2 Top */
134#define OpCode_FDSelect Make_OpCode_ESC(37) /* CFF Top_CID, CFF2 Top */
135#define OpCode_FontName Make_OpCode_ESC(38) /* CFF Top_CID */
136
137
138/* === CharString operators === */
139
140#define OpCode_hstem 1 /* CFF, CFF2 */
141#define OpCode_Reserved2 2
142#define OpCode_vstem 3 /* CFF, CFF2 */
143#define OpCode_vmoveto 4 /* CFF, CFF2 */
144#define OpCode_rlineto 5 /* CFF, CFF2 */
145#define OpCode_hlineto 6 /* CFF, CFF2 */
146#define OpCode_vlineto 7 /* CFF, CFF2 */
147#define OpCode_rrcurveto 8 /* CFF, CFF2 */
148#define OpCode_Reserved9 9
149#define OpCode_callsubr 10 /* CFF, CFF2 */
150#define OpCode_return 11 /* CFF */
151//#define OpCode_escape 12 /* CFF, CFF2 */
152#define OpCode_Reserved13 13
153#define OpCode_endchar 14 /* CFF */
154#define OpCode_vsindexcs 15 /* CFF2 */
155#define OpCode_blendcs 16 /* CFF2 */
156#define OpCode_Reserved17 17
157#define OpCode_hstemhm 18 /* CFF, CFF2 */
158#define OpCode_hintmask 19 /* CFF, CFF2 */
159#define OpCode_cntrmask 20 /* CFF, CFF2 */
160#define OpCode_rmoveto 21 /* CFF, CFF2 */
161#define OpCode_hmoveto 22 /* CFF, CFF2 */
162#define OpCode_vstemhm 23 /* CFF, CFF2 */
163#define OpCode_rcurveline 24 /* CFF, CFF2 */
164#define OpCode_rlinecurve 25 /* CFF, CFF2 */
165#define OpCode_vvcurveto 26 /* CFF, CFF2 */
166#define OpCode_hhcurveto 27 /* CFF, CFF2 */
167//#define OpCode_shortint 28 /* CFF, CFF2 */
168#define OpCode_callgsubr 29 /* CFF, CFF2 */
169#define OpCode_vhcurveto 30 /* CFF, CFF2 */
170#define OpCode_hvcurveto 31 /* CFF, CFF2 */
171
172#define OpCode_fixedcs 255 /* 32-bit fixed */
173
174/* Two byte escape operators 12, (0-41) */
175#define OpCode_dotsection Make_OpCode_ESC(0) /* CFF (obsoleted) */
176#define OpCode_ReservedESC1 Make_OpCode_ESC(1)
177#define OpCode_ReservedESC2 Make_OpCode_ESC(2)
178#define OpCode_and Make_OpCode_ESC(3) /* CFF */
179#define OpCode_or Make_OpCode_ESC(4) /* CFF */
180#define OpCode_not Make_OpCode_ESC(5) /* CFF */
181#define OpCode_ReservedESC6 Make_OpCode_ESC(6)
182#define OpCode_ReservedESC7 Make_OpCode_ESC(7)
183#define OpCode_ReservedESC8 Make_OpCode_ESC(8)
184#define OpCode_abs Make_OpCode_ESC(9) /* CFF */
185#define OpCode_add Make_OpCode_ESC(10) /* CFF */
186#define OpCode_sub Make_OpCode_ESC(11) /* CFF */
187#define OpCode_div Make_OpCode_ESC(12) /* CFF */
188#define OpCode_ReservedESC13 Make_OpCode_ESC(13)
189#define OpCode_neg Make_OpCode_ESC(14) /* CFF */
190#define OpCode_eq Make_OpCode_ESC(15) /* CFF */
191#define OpCode_ReservedESC16 Make_OpCode_ESC(16)
192#define OpCode_ReservedESC17 Make_OpCode_ESC(17)
193#define OpCode_drop Make_OpCode_ESC(18) /* CFF */
194#define OpCode_ReservedESC19 Make_OpCode_ESC(19)
195#define OpCode_put Make_OpCode_ESC(20) /* CFF */
196#define OpCode_get Make_OpCode_ESC(21) /* CFF */
197#define OpCode_ifelse Make_OpCode_ESC(22) /* CFF */
198#define OpCode_random Make_OpCode_ESC(23) /* CFF */
199#define OpCode_mul Make_OpCode_ESC(24) /* CFF */
200//#define OpCode_reservedESC25 Make_OpCode_ESC(25)
201#define OpCode_sqrt Make_OpCode_ESC(26) /* CFF */
202#define OpCode_dup Make_OpCode_ESC(27) /* CFF */
203#define OpCode_exch Make_OpCode_ESC(28) /* CFF */
204#define OpCode_index Make_OpCode_ESC(29) /* CFF */
205#define OpCode_roll Make_OpCode_ESC(30) /* CFF */
206#define OpCode_reservedESC31 Make_OpCode_ESC(31)
207#define OpCode_reservedESC32 Make_OpCode_ESC(32)
208#define OpCode_reservedESC33 Make_OpCode_ESC(33)
209#define OpCode_hflex Make_OpCode_ESC(34) /* CFF, CFF2 */
210#define OpCode_flex Make_OpCode_ESC(35) /* CFF, CFF2 */
211#define OpCode_hflex1 Make_OpCode_ESC(36) /* CFF, CFF2 */
212#define OpCode_flex1 Make_OpCode_ESC(37) /* CFF, CFF2 */
213
214
215#define OpCode_Invalid 0xFFFFu
216
217
218struct number_t
219{
220 void init () { set_real (0.0); }
221 void fini () {}
222
223 void set_int (int v) { value = v; }
224 int to_int () const { return value; }
225
226 void set_fixed (int32_t v) { value = v / 65536.0; }
227 int32_t to_fixed () const { return value * 65536.0; }
228
229 void set_real (double v) { value = v; }
230 double to_real () const { return value; }
231
232 bool in_int_range () const
233 { return ((double) (int16_t) to_int () == value); }
234
235 bool operator > (const number_t &n) const { return value > n.to_real (); }
236 bool operator < (const number_t &n) const { return n > *this; }
237 bool operator >= (const number_t &n) const { return !(*this < n); }
238 bool operator <= (const number_t &n) const { return !(*this > n); }
239
240 const number_t &operator += (const number_t &n)
241 {
242 set_real (to_real () + n.to_real ());
243
244 return *this;
245 }
246
247 protected:
248 double value;
249};
250
251/* byte string */
252struct UnsizedByteStr : UnsizedArrayOf <HBUINT8>
253{
254 // encode 2-byte int (Dict/CharString) or 4-byte int (Dict)
255 template <typename T, typename V>
256 static bool serialize_int (hb_serialize_context_t *c, op_code_t intOp, V value)
257 {
258 TRACE_SERIALIZE (this);
259
260 HBUINT8 *p = c->allocate_size<HBUINT8> (1);
261 if (unlikely (!p)) return_trace (false);
262 *p = intOp;
263
264 T *ip = c->allocate_size<T> (T::static_size);
265 if (unlikely (!ip)) return_trace (false);
266 return_trace (c->check_assign (*ip, value));
267 }
268
269 template <typename V>
270 static bool serialize_int4 (hb_serialize_context_t *c, V value)
271 { return serialize_int<HBINT32> (c, OpCode_longintdict, value); }
272
273 template <typename V>
274 static bool serialize_int2 (hb_serialize_context_t *c, V value)
275 { return serialize_int<HBINT16> (c, OpCode_shortint, value); }
276
277 /* Defining null_size allows a Null object may be created. Should be safe because:
278 * A descendent struct Dict uses a Null pointer to indicate a missing table,
279 * checked before access.
280 * byte_str_t, a wrapper struct pairing a byte pointer along with its length, always
281 * checks the length before access. A Null pointer is used as the initial pointer
282 * along with zero length by the default ctor.
283 */
284 DEFINE_SIZE_MIN(0);
285};
286
287/* Holder of a section of byte string within a CFFIndex entry */
288struct byte_str_t : hb_ubytes_t
289{
290 byte_str_t ()
291 : hb_ubytes_t () {}
292 byte_str_t (const UnsizedByteStr& s, unsigned int l)
293 : hb_ubytes_t ((const unsigned char*)&s, l) {}
294 byte_str_t (const unsigned char *s, unsigned int l)
295 : hb_ubytes_t (s, l) {}
296 byte_str_t (const hb_ubytes_t &ub) /* conversion from hb_ubytes_t */
297 : hb_ubytes_t (ub) {}
298
299 /* sub-string */
300 byte_str_t sub_str (unsigned int offset, unsigned int len_) const
301 { return byte_str_t (hb_ubytes_t::sub_array (offset, len_)); }
302
303 bool check_limit (unsigned int offset, unsigned int count) const
304 { return (offset + count <= length); }
305};
306
307/* A byte string associated with the current offset and an error condition */
308struct byte_str_ref_t
309{
310 byte_str_ref_t () { init (); }
311
312 void init ()
313 {
314 str = byte_str_t ();
315 offset = 0;
316 error = false;
317 }
318
319 void fini () {}
320
321 byte_str_ref_t (const byte_str_t &str_, unsigned int offset_ = 0)
322 : str (str_), offset (offset_), error (false) {}
323
324 void reset (const byte_str_t &str_, unsigned int offset_ = 0)
325 {
326 str = str_;
327 offset = offset_;
328 error = false;
329 }
330
331 const unsigned char& operator [] (int i) {
332 if (unlikely ((unsigned int) (offset + i) >= str.length))
333 {
334 set_error ();
335 return Null (unsigned char);
336 }
337 return str[offset + i];
338 }
339
340 /* Conversion to byte_str_t */
341 operator byte_str_t () const { return str.sub_str (offset, str.length - offset); }
342
343 byte_str_t sub_str (unsigned int offset_, unsigned int len_) const
344 { return str.sub_str (offset_, len_); }
345
346 bool avail (unsigned int count=1) const
347 { return (!in_error () && str.check_limit (offset, count)); }
348 void inc (unsigned int count=1)
349 {
350 if (likely (!in_error () && (offset <= str.length) && (offset + count <= str.length)))
351 {
352 offset += count;
353 }
354 else
355 {
356 offset = str.length;
357 set_error ();
358 }
359 }
360
361 void set_error () { error = true; }
362 bool in_error () const { return error; }
363
364 byte_str_t str;
365 unsigned int offset; /* beginning of the sub-string within str */
366
367 protected:
368 bool error;
369};
370
371typedef hb_vector_t<byte_str_t> byte_str_array_t;
372
373/* stack */
374template <typename ELEM, int LIMIT>
375struct cff_stack_t
376{
377 void init ()
378 {
379 error = false;
380 count = 0;
381 elements.init ();
382 elements.resize (kSizeLimit);
383 for (unsigned int i = 0; i < elements.length; i++)
384 elements[i].init ();
385 }
386 void fini () { elements.fini_deep (); }
387
388 ELEM& operator [] (unsigned int i)
389 {
390 if (unlikely (i >= count)) set_error ();
391 return elements[i];
392 }
393
394 void push (const ELEM &v)
395 {
396 if (likely (count < elements.length))
397 elements[count++] = v;
398 else
399 set_error ();
400 }
401 ELEM &push ()
402 {
403 if (likely (count < elements.length))
404 return elements[count++];
405 else
406 {
407 set_error ();
408 return Crap (ELEM);
409 }
410 }
411
412 ELEM& pop ()
413 {
414 if (likely (count > 0))
415 return elements[--count];
416 else
417 {
418 set_error ();
419 return Crap (ELEM);
420 }
421 }
422 void pop (unsigned int n)
423 {
424 if (likely (count >= n))
425 count -= n;
426 else
427 set_error ();
428 }
429
430 const ELEM& peek ()
431 {
432 if (unlikely (count < 0))
433 {
434 set_error ();
435 return Null (ELEM);
436 }
437 return elements[count - 1];
438 }
439
440 void unpop ()
441 {
442 if (likely (count < elements.length))
443 count++;
444 else
445 set_error ();
446 }
447
448 void clear () { count = 0; }
449
450 bool in_error () const { return (error || elements.in_error ()); }
451 void set_error () { error = true; }
452
453 unsigned int get_count () const { return count; }
454 bool is_empty () const { return !count; }
455
456 static constexpr unsigned kSizeLimit = LIMIT;
457
458 protected:
459 bool error;
460 unsigned int count;
461 hb_vector_t<ELEM> elements;
462};
463
464/* argument stack */
465template <typename ARG=number_t>
466struct arg_stack_t : cff_stack_t<ARG, 513>
467{
468 void push_int (int v)
469 {
470 ARG &n = S::push ();
471 n.set_int (v);
472 }
473
474 void push_fixed (int32_t v)
475 {
476 ARG &n = S::push ();
477 n.set_fixed (v);
478 }
479
480 void push_real (double v)
481 {
482 ARG &n = S::push ();
483 n.set_real (v);
484 }
485
486 ARG& pop_num () { return this->pop (); }
487
488 int pop_int () { return this->pop ().to_int (); }
489
490 unsigned int pop_uint ()
491 {
492 int i = pop_int ();
493 if (unlikely (i < 0))
494 {
495 i = 0;
496 S::set_error ();
497 }
498 return (unsigned) i;
499 }
500
501 void push_longint_from_substr (byte_str_ref_t& str_ref)
502 {
503 push_int ((str_ref[0] << 24) | (str_ref[1] << 16) | (str_ref[2] << 8) | (str_ref[3]));
504 str_ref.inc (4);
505 }
506
507 bool push_fixed_from_substr (byte_str_ref_t& str_ref)
508 {
509 if (unlikely (!str_ref.avail (4)))
510 return false;
511 push_fixed ((int32_t)*(const HBUINT32*)&str_ref[0]);
512 str_ref.inc (4);
513 return true;
514 }
515
516 hb_array_t<const ARG> get_subarray (unsigned int start) const
517 { return S::elements.sub_array (start); }
518
519 private:
520 typedef cff_stack_t<ARG, 513> S;
521};
522
523/* an operator prefixed by its operands in a byte string */
524struct op_str_t
525{
526 void init () {}
527 void fini () {}
528
529 op_code_t op;
530 byte_str_t str;
531};
532
533/* base of OP_SERIALIZER */
534struct op_serializer_t
535{
536 protected:
537 bool copy_opstr (hb_serialize_context_t *c, const op_str_t& opstr) const
538 {
539 TRACE_SERIALIZE (this);
540
541 HBUINT8 *d = c->allocate_size<HBUINT8> (opstr.str.length);
542 if (unlikely (!d)) return_trace (false);
543 memcpy (d, &opstr.str[0], opstr.str.length);
544 return_trace (true);
545 }
546};
547
548template <typename VAL>
549struct parsed_values_t
550{
551 void init ()
552 {
553 opStart = 0;
554 values.init ();
555 }
556 void fini () { values.fini_deep (); }
557
558 void add_op (op_code_t op, const byte_str_ref_t& str_ref = byte_str_ref_t ())
559 {
560 VAL *val = values.push ();
561 val->op = op;
562 val->str = str_ref.str.sub_str (opStart, str_ref.offset - opStart);
563 opStart = str_ref.offset;
564 }
565
566 void add_op (op_code_t op, const byte_str_ref_t& str_ref, const VAL &v)
567 {
568 VAL *val = values.push (v);
569 val->op = op;
570 val->str = str_ref.sub_str ( opStart, str_ref.offset - opStart);
571 opStart = str_ref.offset;
572 }
573
574 bool has_op (op_code_t op) const
575 {
576 for (unsigned int i = 0; i < get_count (); i++)
577 if (get_value (i).op == op) return true;
578 return false;
579 }
580
581 unsigned get_count () const { return values.length; }
582 const VAL &get_value (unsigned int i) const { return values[i]; }
583 const VAL &operator [] (unsigned int i) const { return get_value (i); }
584
585 unsigned int opStart;
586 hb_vector_t<VAL> values;
587};
588
589template <typename ARG=number_t>
590struct interp_env_t
591{
592 void init (const byte_str_t &str_)
593 {
594 str_ref.reset (str_);
595 argStack.init ();
596 error = false;
597 }
598 void fini () { argStack.fini (); }
599
600 bool in_error () const
601 { return error || str_ref.in_error () || argStack.in_error (); }
602
603 void set_error () { error = true; }
604
605 op_code_t fetch_op ()
606 {
607 op_code_t op = OpCode_Invalid;
608 if (unlikely (!str_ref.avail ()))
609 return OpCode_Invalid;
610 op = (op_code_t)(unsigned char)str_ref[0];
611 if (op == OpCode_escape) {
612 if (unlikely (!str_ref.avail ()))
613 return OpCode_Invalid;
614 op = Make_OpCode_ESC(str_ref[1]);
615 str_ref.inc ();
616 }
617 str_ref.inc ();
618 return op;
619 }
620
621 const ARG& eval_arg (unsigned int i) { return argStack[i]; }
622
623 ARG& pop_arg () { return argStack.pop (); }
624 void pop_n_args (unsigned int n) { argStack.pop (n); }
625
626 void clear_args () { pop_n_args (argStack.get_count ()); }
627
628 byte_str_ref_t
629 str_ref;
630 arg_stack_t<ARG>
631 argStack;
632 protected:
633 bool error;
634};
635
636typedef interp_env_t<> num_interp_env_t;
637
638template <typename ARG=number_t>
639struct opset_t
640{
641 static void process_op (op_code_t op, interp_env_t<ARG>& env)
642 {
643 switch (op) {
644 case OpCode_shortint:
645 env.argStack.push_int ((int16_t)((env.str_ref[0] << 8) | env.str_ref[1]));
646 env.str_ref.inc (2);
647 break;
648
649 case OpCode_TwoBytePosInt0: case OpCode_TwoBytePosInt1:
650 case OpCode_TwoBytePosInt2: case OpCode_TwoBytePosInt3:
651 env.argStack.push_int ((int16_t)((op - OpCode_TwoBytePosInt0) * 256 + env.str_ref[0] + 108));
652 env.str_ref.inc ();
653 break;
654
655 case OpCode_TwoByteNegInt0: case OpCode_TwoByteNegInt1:
656 case OpCode_TwoByteNegInt2: case OpCode_TwoByteNegInt3:
657 env.argStack.push_int ((-(int16_t)(op - OpCode_TwoByteNegInt0) * 256 - env.str_ref[0] - 108));
658 env.str_ref.inc ();
659 break;
660
661 default:
662 /* 1-byte integer */
663 if (likely ((OpCode_OneByteIntFirst <= op) && (op <= OpCode_OneByteIntLast)))
664 {
665 env.argStack.push_int ((int)op - 139);
666 } else {
667 /* invalid unknown operator */
668 env.clear_args ();
669 env.set_error ();
670 }
671 break;
672 }
673 }
674};
675
676template <typename ENV>
677struct interpreter_t
678{
679 ~interpreter_t() { fini (); }
680
681 void fini () { env.fini (); }
682
683 ENV env;
684};
685
686} /* namespace CFF */
687
688#endif /* HB_CFF_INTERP_COMMON_HH */
689