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
29 namespace CFF {
30
31 using namespace OT;
32
33 typedef 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
93 inline op_code_t Unmake_OpCode_ESC (op_code_t op) { return (op_code_t)(op - OpCode_ESC_Base); }
94 inline bool Is_OpCode_ESC (op_code_t op) { return op >= OpCode_ESC_Base; }
95 inline 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
218 struct number_t
219 {
220 void init () { set_real (0.0); }
221 void fini () {}
222
223 void set_int (int v) { value = (double) v; }
224 int to_int () const { return (int) value; }
225
226 void set_fixed (int32_t v) { value = v / 65536.0; }
227 int32_t to_fixed () const { return (int32_t) (value * 65536.0); }
228
229 void set_real (double v) { value = v; }
230 double to_real () const { return value; }
231
232 int ceil () const { return (int) ::ceil (value); }
233 int floor () const { return (int) ::floor (value); }
234
235 bool in_int_range () const
236 { return ((double) (int16_t) to_int () == value); }
237
238 bool operator > (const number_t &n) const
239 { return value > n.to_real (); }
240
241 bool operator < (const number_t &n) const
242 { return n > *this; }
243
244 bool operator >= (const number_t &n) const
245 { return !(*this < n); }
246
247 bool operator <= (const number_t &n) const
248 { return !(*this > n); }
249
250 const number_t &operator += (const number_t &n)
251 {
252 set_real (to_real () + n.to_real ());
253
254 return *this;
255 }
256
257 protected:
258 double value;
259 };
260
261 /* byte string */
262 struct UnsizedByteStr : UnsizedArrayOf <HBUINT8>
263 {
264 // encode 2-byte int (Dict/CharString) or 4-byte int (Dict)
265 template <typename INTTYPE, int minVal, int maxVal>
266 static bool serialize_int (hb_serialize_context_t *c, op_code_t intOp, int value)
267 {
268 TRACE_SERIALIZE (this);
269
270 if (unlikely ((value < minVal || value > maxVal)))
271 return_trace (false);
272
273 HBUINT8 *p = c->allocate_size<HBUINT8> (1);
274 if (unlikely (p == nullptr)) return_trace (false);
275 p->set (intOp);
276
277 INTTYPE *ip = c->allocate_size<INTTYPE> (INTTYPE::static_size);
278 if (unlikely (ip == nullptr)) return_trace (false);
279 ip->set ((unsigned int)value);
280
281 return_trace (true);
282 }
283
284 static bool serialize_int4 (hb_serialize_context_t *c, int value)
285 { return serialize_int<HBUINT32, 0, 0x7FFFFFFF> (c, OpCode_longintdict, value); }
286
287 static bool serialize_int2 (hb_serialize_context_t *c, int value)
288 { return serialize_int<HBUINT16, 0, 0x7FFF> (c, OpCode_shortint, value); }
289
290 /* Defining null_size allows a Null object may be created. Should be safe because:
291 * A descendent struct Dict uses a Null pointer to indicate a missing table,
292 * checked before access.
293 * byte_str_t, a wrapper struct pairing a byte pointer along with its length, always
294 * checks the length before access. A Null pointer is used as the initial pointer
295 * along with zero length by the default ctor.
296 */
297 DEFINE_SIZE_MIN(0);
298 };
299
300 /* Holder of a section of byte string within a CFFIndex entry */
301 struct byte_str_t : hb_ubytes_t
302 {
303 byte_str_t ()
304 : hb_ubytes_t () {}
305 byte_str_t (const UnsizedByteStr& s, unsigned int l)
306 : hb_ubytes_t ((const unsigned char*)&s, l) {}
307 byte_str_t (const unsigned char *s, unsigned int l)
308 : hb_ubytes_t (s, l) {}
309 byte_str_t (const hb_ubytes_t &ub) /* conversion from hb_ubytes_t */
310 : hb_ubytes_t (ub) {}
311
312 /* sub-string */
313 byte_str_t sub_str (unsigned int offset, unsigned int len_) const
314 { return byte_str_t (hb_ubytes_t::sub_array (offset, len_)); }
315
316 bool check_limit (unsigned int offset, unsigned int count) const
317 { return (offset + count <= length); }
318 };
319
320 /* A byte string associated with the current offset and an error condition */
321 struct byte_str_ref_t
322 {
323 byte_str_ref_t ()
324 { init (); }
325
326 void init ()
327 {
328 str = byte_str_t ();
329 offset = 0;
330 error = false;
331 }
332
333 void fini () {}
334
335 byte_str_ref_t (const byte_str_t &str_, unsigned int offset_ = 0)
336 : str (str_), offset (offset_), error (false) {}
337
338 void reset (const byte_str_t &str_, unsigned int offset_ = 0)
339 {
340 str = str_;
341 offset = offset_;
342 error = false;
343 }
344
345 const unsigned char& operator [] (int i) {
346 if (unlikely ((unsigned int)(offset + i) >= str.length))
347 {
348 set_error ();
349 return Null(unsigned char);
350 }
351 else
352 return str[offset + i];
353 }
354
355 /* Conversion to byte_str_t */
356 operator byte_str_t () const { return str.sub_str (offset, str.length - offset); }
357
358 byte_str_t sub_str (unsigned int offset_, unsigned int len_) const
359 { return str.sub_str (offset_, len_); }
360
361 bool avail (unsigned int count=1) const
362 {
363 return (!in_error () && str.check_limit (offset, count));
364 }
365 void inc (unsigned int count=1)
366 {
367 if (likely (!in_error () && (offset <= str.length) && (offset + count <= str.length)))
368 {
369 offset += count;
370 }
371 else
372 {
373 offset = str.length;
374 set_error ();
375 }
376 }
377
378 void set_error () { error = true; }
379 bool in_error () const { return error; }
380
381 byte_str_t str;
382 unsigned int offset; /* beginning of the sub-string within str */
383
384 protected:
385 bool error;
386 };
387
388 typedef hb_vector_t<byte_str_t> byte_str_array_t;
389
390 /* stack */
391 template <typename ELEM, int LIMIT>
392 struct stack_t
393 {
394 void init ()
395 {
396 error = false;
397 count = 0;
398 elements.init ();
399 elements.resize (kSizeLimit);
400 for (unsigned int i = 0; i < elements.length; i++)
401 elements[i].init ();
402 }
403
404 void fini ()
405 {
406 elements.fini_deep ();
407 }
408
409 ELEM& operator [] (unsigned int i)
410 {
411 if (unlikely (i >= count)) set_error ();
412 return elements[i];
413 }
414
415 void push (const ELEM &v)
416 {
417 if (likely (count < elements.length))
418 elements[count++] = v;
419 else
420 set_error ();
421 }
422
423 ELEM &push ()
424 {
425 if (likely (count < elements.length))
426 return elements[count++];
427 else
428 {
429 set_error ();
430 return Crap(ELEM);
431 }
432 }
433
434 ELEM& pop ()
435 {
436 if (likely (count > 0))
437 return elements[--count];
438 else
439 {
440 set_error ();
441 return Crap(ELEM);
442 }
443 }
444
445 void pop (unsigned int n)
446 {
447 if (likely (count >= n))
448 count -= n;
449 else
450 set_error ();
451 }
452
453 const ELEM& peek ()
454 {
455 if (likely (count > 0))
456 return elements[count-1];
457 else
458 {
459 set_error ();
460 return Null(ELEM);
461 }
462 }
463
464 void unpop ()
465 {
466 if (likely (count < elements.length))
467 count++;
468 else
469 set_error ();
470 }
471
472 void clear () { count = 0; }
473
474 bool in_error () const { return (error || elements.in_error ()); }
475 void set_error () { error = true; }
476
477 unsigned int get_count () const { return count; }
478 bool is_empty () const { return count == 0; }
479
480 static constexpr unsigned kSizeLimit = LIMIT;
481
482 protected:
483 bool error;
484 unsigned int count;
485 hb_vector_t<ELEM> elements;
486 };
487
488 /* argument stack */
489 template <typename ARG=number_t>
490 struct arg_stack_t : stack_t<ARG, 513>
491 {
492 void push_int (int v)
493 {
494 ARG &n = S::push ();
495 n.set_int (v);
496 }
497
498 void push_fixed (int32_t v)
499 {
500 ARG &n = S::push ();
501 n.set_fixed (v);
502 }
503
504 void push_real (double v)
505 {
506 ARG &n = S::push ();
507 n.set_real (v);
508 }
509
510 ARG& pop_num () { return this->pop (); }
511
512 int pop_int () { return this->pop ().to_int (); }
513
514 unsigned int pop_uint ()
515 {
516 int i = pop_int ();
517 if (unlikely (i < 0))
518 {
519 i = 0;
520 S::set_error ();
521 }
522 return (unsigned)i;
523 }
524
525 void push_longint_from_substr (byte_str_ref_t& str_ref)
526 {
527 push_int ((str_ref[0] << 24) | (str_ref[1] << 16) | (str_ref[2] << 8) | (str_ref[3]));
528 str_ref.inc (4);
529 }
530
531 bool push_fixed_from_substr (byte_str_ref_t& str_ref)
532 {
533 if (unlikely (!str_ref.avail (4)))
534 return false;
535 push_fixed ((int32_t)*(const HBUINT32*)&str_ref[0]);
536 str_ref.inc (4);
537 return true;
538 }
539
540 hb_array_t<const ARG> get_subarray (unsigned int start) const
541 {
542 return S::elements.sub_array (start);
543 }
544
545 private:
546 typedef stack_t<ARG, 513> S;
547 };
548
549 /* an operator prefixed by its operands in a byte string */
550 struct op_str_t
551 {
552 void init () {}
553 void fini () {}
554
555 op_code_t op;
556 byte_str_t str;
557 };
558
559 /* base of OP_SERIALIZER */
560 struct op_serializer_t
561 {
562 protected:
563 bool copy_opstr (hb_serialize_context_t *c, const op_str_t& opstr) const
564 {
565 TRACE_SERIALIZE (this);
566
567 HBUINT8 *d = c->allocate_size<HBUINT8> (opstr.str.length);
568 if (unlikely (d == nullptr)) return_trace (false);
569 memcpy (d, &opstr.str[0], opstr.str.length);
570 return_trace (true);
571 }
572 };
573
574 template <typename VAL>
575 struct parsed_values_t
576 {
577 void init ()
578 {
579 opStart = 0;
580 values.init ();
581 }
582 void fini () { values.fini_deep (); }
583
584 void add_op (op_code_t op, const byte_str_ref_t& str_ref = byte_str_ref_t ())
585 {
586 VAL *val = values.push ();
587 val->op = op;
588 val->str = str_ref.str.sub_str (opStart, str_ref.offset - opStart);
589 opStart = str_ref.offset;
590 }
591
592 void add_op (op_code_t op, const byte_str_ref_t& str_ref, const VAL &v)
593 {
594 VAL *val = values.push (v);
595 val->op = op;
596 val->str = str_ref.sub_str ( opStart, str_ref.offset - opStart);
597 opStart = str_ref.offset;
598 }
599
600 bool has_op (op_code_t op) const
601 {
602 for (unsigned int i = 0; i < get_count (); i++)
603 if (get_value (i).op == op) return true;
604 return false;
605 }
606
607 unsigned get_count () const { return values.length; }
608 const VAL &get_value (unsigned int i) const { return values[i]; }
609 const VAL &operator [] (unsigned int i) const { return get_value (i); }
610
611 unsigned int opStart;
612 hb_vector_t<VAL> values;
613 };
614
615 template <typename ARG=number_t>
616 struct interp_env_t
617 {
618 void init (const byte_str_t &str_)
619 {
620 str_ref.reset (str_);
621 argStack.init ();
622 error = false;
623 }
624 void fini () { argStack.fini (); }
625
626 bool in_error () const
627 { return error || str_ref.in_error () || argStack.in_error (); }
628
629 void set_error () { error = true; }
630
631 op_code_t fetch_op ()
632 {
633 op_code_t op = OpCode_Invalid;
634 if (unlikely (!str_ref.avail ()))
635 return OpCode_Invalid;
636 op = (op_code_t)(unsigned char)str_ref[0];
637 if (op == OpCode_escape) {
638 if (unlikely (!str_ref.avail ()))
639 return OpCode_Invalid;
640 op = Make_OpCode_ESC(str_ref[1]);
641 str_ref.inc ();
642 }
643 str_ref.inc ();
644 return op;
645 }
646
647 const ARG& eval_arg (unsigned int i)
648 {
649 return argStack[i];
650 }
651
652 ARG& pop_arg ()
653 {
654 return argStack.pop ();
655 }
656
657 void pop_n_args (unsigned int n)
658 {
659 argStack.pop (n);
660 }
661
662 void clear_args ()
663 {
664 pop_n_args (argStack.get_count ());
665 }
666
667 byte_str_ref_t str_ref;
668 arg_stack_t<ARG> argStack;
669 protected:
670 bool error;
671 };
672
673 typedef interp_env_t<> num_interp_env_t;
674
675 template <typename ARG=number_t>
676 struct opset_t
677 {
678 static void process_op (op_code_t op, interp_env_t<ARG>& env)
679 {
680 switch (op) {
681 case OpCode_shortint:
682 env.argStack.push_int ((int16_t)((env.str_ref[0] << 8) | env.str_ref[1]));
683 env.str_ref.inc (2);
684 break;
685
686 case OpCode_TwoBytePosInt0: case OpCode_TwoBytePosInt1:
687 case OpCode_TwoBytePosInt2: case OpCode_TwoBytePosInt3:
688 env.argStack.push_int ((int16_t)((op - OpCode_TwoBytePosInt0) * 256 + env.str_ref[0] + 108));
689 env.str_ref.inc ();
690 break;
691
692 case OpCode_TwoByteNegInt0: case OpCode_TwoByteNegInt1:
693 case OpCode_TwoByteNegInt2: case OpCode_TwoByteNegInt3:
694 env.argStack.push_int ((int16_t)(-(op - OpCode_TwoByteNegInt0) * 256 - env.str_ref[0] - 108));
695 env.str_ref.inc ();
696 break;
697
698 default:
699 /* 1-byte integer */
700 if (likely ((OpCode_OneByteIntFirst <= op) && (op <= OpCode_OneByteIntLast)))
701 {
702 env.argStack.push_int ((int)op - 139);
703 } else {
704 /* invalid unknown operator */
705 env.clear_args ();
706 env.set_error ();
707 }
708 break;
709 }
710 }
711 };
712
713 template <typename ENV>
714 struct interpreter_t {
715
716 ~interpreter_t() { fini (); }
717
718 void fini () { env.fini (); }
719
720 ENV env;
721 };
722
723 } /* namespace CFF */
724
725 #endif /* HB_CFF_INTERP_COMMON_HH */