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/cvs/JSON-XS/XS.xs
Revision: 1.41
Committed: Sat Jun 23 22:53:16 2007 UTC (16 years, 10 months ago) by root
Branch: MAIN
Changes since 1.40: +6 -0 lines
Log Message:
*** empty log message ***

File Contents

# Content
1 #include "EXTERN.h"
2 #include "perl.h"
3 #include "XSUB.h"
4
5 #include "assert.h"
6 #include "string.h"
7 #include "stdlib.h"
8 #include "stdio.h"
9
10 #if defined(__BORLANDC__) || defined(_MSC_VER)
11 # define snprintf _snprintf // C compilers have this in stdio.h
12 #endif
13
14 // some old perls do not have this, try to make it work, no
15 // guarentees, though.
16 #ifndef UTF8_MAXBYTES
17 # define UTF8_MAXBYTES 13
18 #endif
19
20 #define F_ASCII 0x00000001UL
21 #define F_LATIN1 0x00000002UL
22 #define F_UTF8 0x00000004UL
23 #define F_INDENT 0x00000008UL
24 #define F_CANONICAL 0x00000010UL
25 #define F_SPACE_BEFORE 0x00000020UL
26 #define F_SPACE_AFTER 0x00000040UL
27 #define F_ALLOW_NONREF 0x00000100UL
28 #define F_SHRINK 0x00000200UL
29 #define F_MAXDEPTH 0xf8000000UL
30 #define S_MAXDEPTH 27
31
32 #define DEC_DEPTH(flags) (1UL << ((flags & F_MAXDEPTH) >> S_MAXDEPTH))
33
34 // F_SELFCONVERT? <=> to_json/toJson
35 // F_BLESSED? <=> { $__class__$ => }
36
37 #define F_PRETTY F_INDENT | F_SPACE_BEFORE | F_SPACE_AFTER
38 #define F_DEFAULT (9UL << S_MAXDEPTH)
39
40 #define INIT_SIZE 32 // initial scalar size to be allocated
41 #define INDENT_STEP 3 // spaces per indentation level
42
43 #define SHORT_STRING_LEN 16384 // special-case strings of up to this size
44
45 #define SB do {
46 #define SE } while (0)
47
48 #if __GNUC__ >= 3
49 # define expect(expr,value) __builtin_expect ((expr),(value))
50 # define inline inline
51 #else
52 # define expect(expr,value) (expr)
53 # define inline static
54 #endif
55
56 #define expect_false(expr) expect ((expr) != 0, 0)
57 #define expect_true(expr) expect ((expr) != 0, 1)
58
59 static HV *json_stash; // JSON::XS::
60
61 /////////////////////////////////////////////////////////////////////////////
62 // utility functions
63
64 static UV *
65 SvJSON (SV *sv)
66 {
67 if (!(SvROK (sv) && SvOBJECT (SvRV (sv)) && SvSTASH (SvRV (sv)) == json_stash))
68 croak ("object is not of type JSON::XS");
69
70 return &SvUVX (SvRV (sv));
71 }
72
73 static void
74 shrink (SV *sv)
75 {
76 sv_utf8_downgrade (sv, 1);
77 if (SvLEN (sv) > SvCUR (sv) + 1)
78 {
79 #ifdef SvPV_shrink_to_cur
80 SvPV_shrink_to_cur (sv);
81 #elif defined (SvPV_renew)
82 SvPV_renew (sv, SvCUR (sv) + 1);
83 #endif
84 }
85 }
86
87 // decode an utf-8 character and return it, or (UV)-1 in
88 // case of an error.
89 // we special-case "safe" characters from U+80 .. U+7FF,
90 // but use the very good perl function to parse anything else.
91 // note that we never call this function for a ascii codepoints
92 inline UV
93 decode_utf8 (unsigned char *s, STRLEN len, STRLEN *clen)
94 {
95 if (expect_false (s[0] > 0xdf || s[0] < 0xc2))
96 return utf8n_to_uvuni (s, len, clen, UTF8_CHECK_ONLY);
97 else if (len > 1 && s[1] >= 0x80 && s[1] <= 0xbf)
98 {
99 *clen = 2;
100 return ((s[0] & 0x1f) << 6) | (s[1] & 0x3f);
101 }
102 else
103 {
104 *clen = (STRLEN)-1;
105 return (UV)-1;
106 }
107 }
108
109 /////////////////////////////////////////////////////////////////////////////
110 // encoder
111
112 // structure used for encoding JSON
113 typedef struct
114 {
115 char *cur; // SvPVX (sv) + current output position
116 char *end; // SvEND (sv)
117 SV *sv; // result scalar
118 U32 flags; // F_*
119 U32 indent; // indentation level
120 U32 maxdepth; // max. indentation/recursion level
121 } enc_t;
122
123 inline void
124 need (enc_t *enc, STRLEN len)
125 {
126 if (expect_false (enc->cur + len >= enc->end))
127 {
128 STRLEN cur = enc->cur - SvPVX (enc->sv);
129 SvGROW (enc->sv, cur + len + 1);
130 enc->cur = SvPVX (enc->sv) + cur;
131 enc->end = SvPVX (enc->sv) + SvLEN (enc->sv) - 1;
132 }
133 }
134
135 inline void
136 encode_ch (enc_t *enc, char ch)
137 {
138 need (enc, 1);
139 *enc->cur++ = ch;
140 }
141
142 static void
143 encode_str (enc_t *enc, char *str, STRLEN len, int is_utf8)
144 {
145 char *end = str + len;
146
147 need (enc, len);
148
149 while (str < end)
150 {
151 unsigned char ch = *(unsigned char *)str;
152
153 if (expect_true (ch >= 0x20 && ch < 0x80)) // most common case
154 {
155 if (expect_false (ch == '"')) // but with slow exceptions
156 {
157 need (enc, len += 1);
158 *enc->cur++ = '\\';
159 *enc->cur++ = '"';
160 }
161 else if (expect_false (ch == '\\'))
162 {
163 need (enc, len += 1);
164 *enc->cur++ = '\\';
165 *enc->cur++ = '\\';
166 }
167 else
168 *enc->cur++ = ch;
169
170 ++str;
171 }
172 else
173 {
174 switch (ch)
175 {
176 case '\010': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'b'; ++str; break;
177 case '\011': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 't'; ++str; break;
178 case '\012': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'n'; ++str; break;
179 case '\014': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'f'; ++str; break;
180 case '\015': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'r'; ++str; break;
181
182 default:
183 {
184 STRLEN clen;
185 UV uch;
186
187 if (is_utf8)
188 {
189 uch = decode_utf8 (str, end - str, &clen);
190 if (clen == (STRLEN)-1)
191 croak ("malformed or illegal unicode character in string [%.11s], cannot convert to JSON", str);
192 }
193 else
194 {
195 uch = ch;
196 clen = 1;
197 }
198
199 if (uch > 0x10FFFFUL)
200 croak ("out of range codepoint (0x%lx) encountered, unrepresentable in JSON", (unsigned long)uch);
201
202 if (uch < 0x80 || enc->flags & F_ASCII || (enc->flags & F_LATIN1 && uch > 0xFF))
203 {
204 if (uch > 0xFFFFUL)
205 {
206 need (enc, len += 11);
207 sprintf (enc->cur, "\\u%04x\\u%04x",
208 (int)((uch - 0x10000) / 0x400 + 0xD800),
209 (int)((uch - 0x10000) % 0x400 + 0xDC00));
210 enc->cur += 12;
211 }
212 else
213 {
214 static char hexdigit [16] = "0123456789abcdef";
215 need (enc, len += 5);
216 *enc->cur++ = '\\';
217 *enc->cur++ = 'u';
218 *enc->cur++ = hexdigit [ uch >> 12 ];
219 *enc->cur++ = hexdigit [(uch >> 8) & 15];
220 *enc->cur++ = hexdigit [(uch >> 4) & 15];
221 *enc->cur++ = hexdigit [(uch >> 0) & 15];
222 }
223
224 str += clen;
225 }
226 else if (enc->flags & F_LATIN1)
227 {
228 *enc->cur++ = uch;
229 str += clen;
230 }
231 else if (is_utf8)
232 {
233 need (enc, len += clen);
234 do
235 {
236 *enc->cur++ = *str++;
237 }
238 while (--clen);
239 }
240 else
241 {
242 need (enc, len += UTF8_MAXBYTES - 1); // never more than 11 bytes needed
243 enc->cur = uvuni_to_utf8_flags (enc->cur, uch, 0);
244 ++str;
245 }
246 }
247 }
248 }
249
250 --len;
251 }
252 }
253
254 inline void
255 encode_indent (enc_t *enc)
256 {
257 if (enc->flags & F_INDENT)
258 {
259 int spaces = enc->indent * INDENT_STEP;
260
261 need (enc, spaces);
262 memset (enc->cur, ' ', spaces);
263 enc->cur += spaces;
264 }
265 }
266
267 inline void
268 encode_space (enc_t *enc)
269 {
270 need (enc, 1);
271 encode_ch (enc, ' ');
272 }
273
274 inline void
275 encode_nl (enc_t *enc)
276 {
277 if (enc->flags & F_INDENT)
278 {
279 need (enc, 1);
280 encode_ch (enc, '\n');
281 }
282 }
283
284 inline void
285 encode_comma (enc_t *enc)
286 {
287 encode_ch (enc, ',');
288
289 if (enc->flags & F_INDENT)
290 encode_nl (enc);
291 else if (enc->flags & F_SPACE_AFTER)
292 encode_space (enc);
293 }
294
295 static void encode_sv (enc_t *enc, SV *sv);
296
297 static void
298 encode_av (enc_t *enc, AV *av)
299 {
300 int i, len = av_len (av);
301
302 if (enc->indent >= enc->maxdepth)
303 croak ("data structure too deep (hit recursion limit)");
304
305 encode_ch (enc, '['); encode_nl (enc);
306 ++enc->indent;
307
308 for (i = 0; i <= len; ++i)
309 {
310 encode_indent (enc);
311 encode_sv (enc, *av_fetch (av, i, 0));
312
313 if (i < len)
314 encode_comma (enc);
315 }
316
317 encode_nl (enc);
318
319 --enc->indent;
320 encode_indent (enc); encode_ch (enc, ']');
321 }
322
323 static void
324 encode_he (enc_t *enc, HE *he)
325 {
326 encode_ch (enc, '"');
327
328 if (HeKLEN (he) == HEf_SVKEY)
329 {
330 SV *sv = HeSVKEY (he);
331 STRLEN len;
332 char *str;
333
334 SvGETMAGIC (sv);
335 str = SvPV (sv, len);
336
337 encode_str (enc, str, len, SvUTF8 (sv));
338 }
339 else
340 encode_str (enc, HeKEY (he), HeKLEN (he), HeKUTF8 (he));
341
342 encode_ch (enc, '"');
343
344 if (enc->flags & F_SPACE_BEFORE) encode_space (enc);
345 encode_ch (enc, ':');
346 if (enc->flags & F_SPACE_AFTER ) encode_space (enc);
347 encode_sv (enc, HeVAL (he));
348 }
349
350 // compare hash entries, used when all keys are bytestrings
351 static int
352 he_cmp_fast (const void *a_, const void *b_)
353 {
354 int cmp;
355
356 HE *a = *(HE **)a_;
357 HE *b = *(HE **)b_;
358
359 STRLEN la = HeKLEN (a);
360 STRLEN lb = HeKLEN (b);
361
362 if (!(cmp = memcmp (HeKEY (a), HeKEY (b), la < lb ? la : lb)))
363 cmp = la - lb;
364
365 return cmp;
366 }
367
368 // compare hash entries, used when some keys are sv's or utf-x
369 static int
370 he_cmp_slow (const void *a, const void *b)
371 {
372 return sv_cmp (HeSVKEY_force (*(HE **)a), HeSVKEY_force (*(HE **)b));
373 }
374
375 static void
376 encode_hv (enc_t *enc, HV *hv)
377 {
378 int count, i;
379
380 if (enc->indent >= enc->maxdepth)
381 croak ("data structure too deep (hit recursion limit)");
382
383 encode_ch (enc, '{'); encode_nl (enc); ++enc->indent;
384
385 if ((count = hv_iterinit (hv)))
386 {
387 // for canonical output we have to sort by keys first
388 // actually, this is mostly due to the stupid so-called
389 // security workaround added somewhere in 5.8.x.
390 // that randomises hash orderings
391 if (enc->flags & F_CANONICAL)
392 {
393 int fast = 1;
394 HE *he;
395 #if defined(__BORLANDC__) || defined(_MSC_VER)
396 HE **hes = _alloca (count * sizeof (HE));
397 #else
398 HE *hes [count]; // if your compiler dies here, you need to enable C99 mode
399 #endif
400
401 i = 0;
402 while ((he = hv_iternext (hv)))
403 {
404 hes [i++] = he;
405 if (HeKLEN (he) < 0 || HeKUTF8 (he))
406 fast = 0;
407 }
408
409 assert (i == count);
410
411 if (fast)
412 qsort (hes, count, sizeof (HE *), he_cmp_fast);
413 else
414 {
415 // hack to forcefully disable "use bytes"
416 COP cop = *PL_curcop;
417 cop.op_private = 0;
418
419 ENTER;
420 SAVETMPS;
421
422 SAVEVPTR (PL_curcop);
423 PL_curcop = &cop;
424
425 qsort (hes, count, sizeof (HE *), he_cmp_slow);
426
427 FREETMPS;
428 LEAVE;
429 }
430
431 for (i = 0; i < count; ++i)
432 {
433 encode_indent (enc);
434 encode_he (enc, hes [i]);
435
436 if (i < count - 1)
437 encode_comma (enc);
438 }
439
440 encode_nl (enc);
441 }
442 else
443 {
444 HE *he = hv_iternext (hv);
445
446 for (;;)
447 {
448 encode_indent (enc);
449 encode_he (enc, he);
450
451 if (!(he = hv_iternext (hv)))
452 break;
453
454 encode_comma (enc);
455 }
456
457 encode_nl (enc);
458 }
459 }
460
461 --enc->indent; encode_indent (enc); encode_ch (enc, '}');
462 }
463
464 // encode objects, arrays and special \0=false and \1=true values.
465 static void
466 encode_rv (enc_t *enc, SV *sv)
467 {
468 svtype svt;
469
470 SvGETMAGIC (sv);
471 svt = SvTYPE (sv);
472
473 if (svt == SVt_PVHV)
474 encode_hv (enc, (HV *)sv);
475 else if (svt == SVt_PVAV)
476 encode_av (enc, (AV *)sv);
477 else if (svt < SVt_PVAV)
478 {
479 if (SvNIOK (sv) && SvIV (sv) == 0)
480 encode_str (enc, "false", 5, 0);
481 else if (SvNIOK (sv) && SvIV (sv) == 1)
482 encode_str (enc, "true", 4, 0);
483 else
484 croak ("cannot encode reference to scalar '%s' unless the scalar is 0 or 1",
485 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
486 }
487 else
488 croak ("encountered %s, but JSON can only represent references to arrays or hashes",
489 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
490 }
491
492 static void
493 encode_sv (enc_t *enc, SV *sv)
494 {
495 SvGETMAGIC (sv);
496
497 if (SvPOKp (sv))
498 {
499 STRLEN len;
500 char *str = SvPV (sv, len);
501 encode_ch (enc, '"');
502 encode_str (enc, str, len, SvUTF8 (sv));
503 encode_ch (enc, '"');
504 }
505 else if (SvNOKp (sv))
506 {
507 // trust that perl will do the right thing w.r.t. JSON syntax.
508 need (enc, NV_DIG + 32);
509 Gconvert (SvNVX (sv), NV_DIG, 0, enc->cur);
510 enc->cur += strlen (enc->cur);
511 }
512 else if (SvIOKp (sv))
513 {
514 // we assume we can always read an IV as a UV
515 if (SvUV (sv) & ~(UV)0x7fff)
516 {
517 // large integer, use the (rather slow) snprintf way.
518 need (enc, sizeof (UV) * 3);
519 enc->cur +=
520 SvIsUV(sv)
521 ? snprintf (enc->cur, sizeof (UV) * 3, "%"UVuf, (UV)SvUVX (sv))
522 : snprintf (enc->cur, sizeof (UV) * 3, "%"IVdf, (IV)SvIVX (sv));
523 }
524 else
525 {
526 // optimise the "small number case"
527 // code will likely be branchless and use only a single multiplication
528 I32 i = SvIV (sv);
529 U32 u;
530 char digit, nz = 0;
531
532 need (enc, 6);
533
534 *enc->cur = '-'; enc->cur += i < 0 ? 1 : 0;
535 u = i < 0 ? -i : i;
536
537 // convert to 4.28 fixed-point representation
538 u = u * ((0xfffffff + 10000) / 10000); // 10**5, 5 fractional digits
539
540 // now output digit by digit, each time masking out the integer part
541 // and multiplying by 5 while moving the decimal point one to the right,
542 // resulting in a net multiplication by 10.
543 // we always write the digit to memory but conditionally increment
544 // the pointer, to ease the usage of conditional move instructions.
545 digit = u >> 28; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0xfffffff) * 5;
546 digit = u >> 27; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x7ffffff) * 5;
547 digit = u >> 26; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x3ffffff) * 5;
548 digit = u >> 25; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x1ffffff) * 5;
549 digit = u >> 24; *enc->cur = digit + '0'; enc->cur += 1; // correctly generate '0'
550 }
551 }
552 else if (SvROK (sv))
553 encode_rv (enc, SvRV (sv));
554 else if (!SvOK (sv))
555 encode_str (enc, "null", 4, 0);
556 else
557 croak ("encountered perl type (%s,0x%x) that JSON cannot handle, you might want to report this",
558 SvPV_nolen (sv), SvFLAGS (sv));
559 }
560
561 static SV *
562 encode_json (SV *scalar, U32 flags)
563 {
564 enc_t enc;
565
566 if (!(flags & F_ALLOW_NONREF) && !SvROK (scalar))
567 croak ("hash- or arrayref expected (not a simple scalar, use allow_nonref to allow this)");
568
569 enc.flags = flags;
570 enc.sv = sv_2mortal (NEWSV (0, INIT_SIZE));
571 enc.cur = SvPVX (enc.sv);
572 enc.end = SvEND (enc.sv);
573 enc.indent = 0;
574 enc.maxdepth = DEC_DEPTH (flags);
575
576 SvPOK_only (enc.sv);
577 encode_sv (&enc, scalar);
578
579 SvCUR_set (enc.sv, enc.cur - SvPVX (enc.sv));
580 *SvEND (enc.sv) = 0; // many xs functions expect a trailing 0 for text strings
581
582 if (!(flags & (F_ASCII | F_LATIN1 | F_UTF8)))
583 SvUTF8_on (enc.sv);
584
585 if (enc.flags & F_SHRINK)
586 shrink (enc.sv);
587
588 return enc.sv;
589 }
590
591 /////////////////////////////////////////////////////////////////////////////
592 // decoder
593
594 // structure used for decoding JSON
595 typedef struct
596 {
597 char *cur; // current parser pointer
598 char *end; // end of input string
599 const char *err; // parse error, if != 0
600 U32 flags; // F_*
601 U32 depth; // recursion depth
602 U32 maxdepth; // recursion depth limit
603 } dec_t;
604
605 inline void
606 decode_ws (dec_t *dec)
607 {
608 for (;;)
609 {
610 char ch = *dec->cur;
611
612 if (ch > 0x20
613 || (ch != 0x20 && ch != 0x0a && ch != 0x0d && ch != 0x09))
614 break;
615
616 ++dec->cur;
617 }
618 }
619
620 #define ERR(reason) SB dec->err = reason; goto fail; SE
621
622 #define EXPECT_CH(ch) SB \
623 if (*dec->cur != ch) \
624 ERR (# ch " expected"); \
625 ++dec->cur; \
626 SE
627
628 #define DEC_INC_DEPTH if (++dec->depth > dec->maxdepth) ERR ("json datastructure exceeds maximum nesting level (set a higher max_depth)")
629 #define DEC_DEC_DEPTH --dec->depth
630
631 static SV *decode_sv (dec_t *dec);
632
633 static signed char decode_hexdigit[256];
634
635 static UV
636 decode_4hex (dec_t *dec)
637 {
638 signed char d1, d2, d3, d4;
639 unsigned char *cur = (unsigned char *)dec->cur;
640
641 d1 = decode_hexdigit [cur [0]]; if (expect_false (d1 < 0)) ERR ("exactly four hexadecimal digits expected");
642 d2 = decode_hexdigit [cur [1]]; if (expect_false (d2 < 0)) ERR ("exactly four hexadecimal digits expected");
643 d3 = decode_hexdigit [cur [2]]; if (expect_false (d3 < 0)) ERR ("exactly four hexadecimal digits expected");
644 d4 = decode_hexdigit [cur [3]]; if (expect_false (d4 < 0)) ERR ("exactly four hexadecimal digits expected");
645
646 dec->cur += 4;
647
648 return ((UV)d1) << 12
649 | ((UV)d2) << 8
650 | ((UV)d3) << 4
651 | ((UV)d4);
652
653 fail:
654 return (UV)-1;
655 }
656
657 static SV *
658 decode_str (dec_t *dec)
659 {
660 SV *sv = 0;
661 int utf8 = 0;
662 char *dec_cur = dec->cur;
663
664 do
665 {
666 char buf [SHORT_STRING_LEN + UTF8_MAXBYTES];
667 char *cur = buf;
668
669 do
670 {
671 unsigned char ch = *(unsigned char *)dec_cur++;
672
673 if (expect_false (ch == '"'))
674 {
675 --dec_cur;
676 break;
677 }
678 else if (expect_false (ch == '\\'))
679 {
680 switch (*dec_cur)
681 {
682 case '\\':
683 case '/':
684 case '"': *cur++ = *dec_cur++; break;
685
686 case 'b': ++dec_cur; *cur++ = '\010'; break;
687 case 't': ++dec_cur; *cur++ = '\011'; break;
688 case 'n': ++dec_cur; *cur++ = '\012'; break;
689 case 'f': ++dec_cur; *cur++ = '\014'; break;
690 case 'r': ++dec_cur; *cur++ = '\015'; break;
691
692 case 'u':
693 {
694 UV lo, hi;
695 ++dec_cur;
696
697 dec->cur = dec_cur;
698 hi = decode_4hex (dec);
699 dec_cur = dec->cur;
700 if (hi == (UV)-1)
701 goto fail;
702
703 // possibly a surrogate pair
704 if (hi >= 0xd800)
705 if (hi < 0xdc00)
706 {
707 if (dec_cur [0] != '\\' || dec_cur [1] != 'u')
708 ERR ("missing low surrogate character in surrogate pair");
709
710 dec_cur += 2;
711
712 dec->cur = dec_cur;
713 lo = decode_4hex (dec);
714 dec_cur = dec->cur;
715 if (lo == (UV)-1)
716 goto fail;
717
718 if (lo < 0xdc00 || lo >= 0xe000)
719 ERR ("surrogate pair expected");
720
721 hi = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000;
722 }
723 else if (hi < 0xe000)
724 ERR ("missing high surrogate character in surrogate pair");
725
726 if (hi >= 0x80)
727 {
728 utf8 = 1;
729
730 cur = (char *)uvuni_to_utf8_flags (cur, hi, 0);
731 }
732 else
733 *cur++ = hi;
734 }
735 break;
736
737 default:
738 --dec_cur;
739 ERR ("illegal backslash escape sequence in string");
740 }
741 }
742 else if (expect_true (ch >= 0x20 && ch <= 0x7f))
743 *cur++ = ch;
744 else if (ch >= 0x80)
745 {
746 STRLEN clen;
747 UV uch;
748
749 --dec_cur;
750
751 uch = decode_utf8 (dec_cur, dec->end - dec_cur, &clen);
752 if (clen == (STRLEN)-1)
753 ERR ("malformed UTF-8 character in JSON string");
754
755 do
756 *cur++ = *dec_cur++;
757 while (--clen);
758
759 utf8 = 1;
760 }
761 else
762 {
763 --dec_cur;
764
765 if (!ch)
766 ERR ("unexpected end of string while parsing JSON string");
767 else
768 ERR ("invalid character encountered while parsing JSON string");
769 }
770 }
771 while (cur < buf + SHORT_STRING_LEN);
772
773 {
774 STRLEN len = cur - buf;
775
776 if (sv)
777 {
778 SvGROW (sv, SvCUR (sv) + len + 1);
779 memcpy (SvPVX (sv) + SvCUR (sv), buf, len);
780 SvCUR_set (sv, SvCUR (sv) + len);
781 }
782 else
783 sv = newSVpvn (buf, len);
784 }
785 }
786 while (*dec_cur != '"');
787
788 ++dec_cur;
789
790 if (sv)
791 {
792 SvPOK_only (sv);
793 *SvEND (sv) = 0;
794
795 if (utf8)
796 SvUTF8_on (sv);
797 }
798 else
799 sv = newSVpvn ("", 0);
800
801 dec->cur = dec_cur;
802 return sv;
803
804 fail:
805 dec->cur = dec_cur;
806 return 0;
807 }
808
809 static SV *
810 decode_num (dec_t *dec)
811 {
812 int is_nv = 0;
813 char *start = dec->cur;
814
815 // [minus]
816 if (*dec->cur == '-')
817 ++dec->cur;
818
819 if (*dec->cur == '0')
820 {
821 ++dec->cur;
822 if (*dec->cur >= '0' && *dec->cur <= '9')
823 ERR ("malformed number (leading zero must not be followed by another digit)");
824 }
825 else if (*dec->cur < '0' || *dec->cur > '9')
826 ERR ("malformed number (no digits after initial minus)");
827 else
828 do
829 {
830 ++dec->cur;
831 }
832 while (*dec->cur >= '0' && *dec->cur <= '9');
833
834 // [frac]
835 if (*dec->cur == '.')
836 {
837 ++dec->cur;
838
839 if (*dec->cur < '0' || *dec->cur > '9')
840 ERR ("malformed number (no digits after decimal point)");
841
842 do
843 {
844 ++dec->cur;
845 }
846 while (*dec->cur >= '0' && *dec->cur <= '9');
847
848 is_nv = 1;
849 }
850
851 // [exp]
852 if (*dec->cur == 'e' || *dec->cur == 'E')
853 {
854 ++dec->cur;
855
856 if (*dec->cur == '-' || *dec->cur == '+')
857 ++dec->cur;
858
859 if (*dec->cur < '0' || *dec->cur > '9')
860 ERR ("malformed number (no digits after exp sign)");
861
862 do
863 {
864 ++dec->cur;
865 }
866 while (*dec->cur >= '0' && *dec->cur <= '9');
867
868 is_nv = 1;
869 }
870
871 if (!is_nv)
872 {
873 // special case the rather common 1..4-digit-int case, assumes 32 bit ints or so
874 if (*start == '-')
875 switch (dec->cur - start)
876 {
877 case 2: return newSViv (-( start [1] - '0' * 1));
878 case 3: return newSViv (-( start [1] * 10 + start [2] - '0' * 11));
879 case 4: return newSViv (-( start [1] * 100 + start [2] * 10 + start [3] - '0' * 111));
880 case 5: return newSViv (-(start [1] * 1000 + start [2] * 100 + start [3] * 10 + start [4] - '0' * 1111));
881 }
882 else
883 switch (dec->cur - start)
884 {
885 case 1: return newSViv ( start [0] - '0' * 1);
886 case 2: return newSViv ( start [0] * 10 + start [1] - '0' * 11);
887 case 3: return newSViv ( start [0] * 100 + start [1] * 10 + start [2] - '0' * 111);
888 case 4: return newSViv ( start [0] * 1000 + start [1] * 100 + start [2] * 10 + start [3] - '0' * 1111);
889 }
890
891 {
892 UV uv;
893 int numtype = grok_number (start, dec->cur - start, &uv);
894 if (numtype & IS_NUMBER_IN_UV)
895 if (numtype & IS_NUMBER_NEG)
896 {
897 if (uv < (UV)IV_MIN)
898 return newSViv (-(IV)uv);
899 }
900 else
901 return newSVuv (uv);
902
903 // here would likely be the place for bigint support
904 }
905 }
906
907 // if we ever support bigint or bigfloat, this is the place for bigfloat
908 return newSVnv (Atof (start));
909
910 fail:
911 return 0;
912 }
913
914 static SV *
915 decode_av (dec_t *dec)
916 {
917 AV *av = newAV ();
918
919 DEC_INC_DEPTH;
920 decode_ws (dec);
921
922 if (*dec->cur == ']')
923 ++dec->cur;
924 else
925 for (;;)
926 {
927 SV *value;
928
929 value = decode_sv (dec);
930 if (!value)
931 goto fail;
932
933 av_push (av, value);
934
935 decode_ws (dec);
936
937 if (*dec->cur == ']')
938 {
939 ++dec->cur;
940 break;
941 }
942
943 if (*dec->cur != ',')
944 ERR (", or ] expected while parsing array");
945
946 ++dec->cur;
947 }
948
949 DEC_DEC_DEPTH;
950 return newRV_noinc ((SV *)av);
951
952 fail:
953 SvREFCNT_dec (av);
954 DEC_DEC_DEPTH;
955 return 0;
956 }
957
958 static SV *
959 decode_hv (dec_t *dec)
960 {
961 HV *hv = newHV ();
962
963 DEC_INC_DEPTH;
964 decode_ws (dec);
965
966 if (*dec->cur == '}')
967 ++dec->cur;
968 else
969 for (;;)
970 {
971 SV *key, *value;
972
973 decode_ws (dec); EXPECT_CH ('"');
974
975 key = decode_str (dec);
976 if (!key)
977 goto fail;
978
979 decode_ws (dec); EXPECT_CH (':');
980
981 value = decode_sv (dec);
982 if (!value)
983 {
984 SvREFCNT_dec (key);
985 goto fail;
986 }
987
988 hv_store_ent (hv, key, value, 0);
989 SvREFCNT_dec (key);
990
991 decode_ws (dec);
992
993 if (*dec->cur == '}')
994 {
995 ++dec->cur;
996 break;
997 }
998
999 if (*dec->cur != ',')
1000 ERR (", or } expected while parsing object/hash");
1001
1002 ++dec->cur;
1003 }
1004
1005 DEC_DEC_DEPTH;
1006 return newRV_noinc ((SV *)hv);
1007
1008 fail:
1009 SvREFCNT_dec (hv);
1010 DEC_DEC_DEPTH;
1011 return 0;
1012 }
1013
1014 static SV *
1015 decode_sv (dec_t *dec)
1016 {
1017 decode_ws (dec);
1018
1019 // the beauty of JSON: you need exactly one character lookahead
1020 // to parse anything.
1021 switch (*dec->cur)
1022 {
1023 case '"': ++dec->cur; return decode_str (dec);
1024 case '[': ++dec->cur; return decode_av (dec);
1025 case '{': ++dec->cur; return decode_hv (dec);
1026
1027 case '-':
1028 case '0': case '1': case '2': case '3': case '4':
1029 case '5': case '6': case '7': case '8': case '9':
1030 return decode_num (dec);
1031
1032 case 't':
1033 if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "true", 4))
1034 {
1035 dec->cur += 4;
1036 return newSViv (1);
1037 }
1038 else
1039 ERR ("'true' expected");
1040
1041 break;
1042
1043 case 'f':
1044 if (dec->end - dec->cur >= 5 && !memcmp (dec->cur, "false", 5))
1045 {
1046 dec->cur += 5;
1047 return newSViv (0);
1048 }
1049 else
1050 ERR ("'false' expected");
1051
1052 break;
1053
1054 case 'n':
1055 if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "null", 4))
1056 {
1057 dec->cur += 4;
1058 return newSVsv (&PL_sv_undef);
1059 }
1060 else
1061 ERR ("'null' expected");
1062
1063 break;
1064
1065 default:
1066 ERR ("malformed JSON string, neither array, object, number, string or atom");
1067 break;
1068 }
1069
1070 fail:
1071 return 0;
1072 }
1073
1074 static SV *
1075 decode_json (SV *string, U32 flags, UV *offset_return)
1076 {
1077 dec_t dec;
1078 UV offset;
1079 SV *sv;
1080
1081 SvGETMAGIC (string);
1082 SvUPGRADE (string, SVt_PV);
1083
1084 if (flags & F_UTF8)
1085 sv_utf8_downgrade (string, 0);
1086 else
1087 sv_utf8_upgrade (string);
1088
1089 SvGROW (string, SvCUR (string) + 1); // should basically be a NOP
1090
1091 dec.flags = flags;
1092 dec.cur = SvPVX (string);
1093 dec.end = SvEND (string);
1094 dec.err = 0;
1095 dec.depth = 0;
1096 dec.maxdepth = DEC_DEPTH (dec.flags);
1097
1098 *dec.end = 0; // this should basically be a nop, too, but make sure it's there
1099 sv = decode_sv (&dec);
1100
1101 if (!(offset_return || !sv))
1102 {
1103 // check for trailing garbage
1104 decode_ws (&dec);
1105
1106 if (*dec.cur)
1107 {
1108 dec.err = "garbage after JSON object";
1109 SvREFCNT_dec (sv);
1110 sv = 0;
1111 }
1112 }
1113
1114 if (offset_return || !sv)
1115 {
1116 offset = dec.flags & F_UTF8
1117 ? dec.cur - SvPVX (string)
1118 : utf8_distance (dec.cur, SvPVX (string));
1119
1120 if (offset_return)
1121 *offset_return = offset;
1122 }
1123
1124 if (!sv)
1125 {
1126 SV *uni = sv_newmortal ();
1127
1128 // horrible hack to silence warning inside pv_uni_display
1129 COP cop = *PL_curcop;
1130 cop.cop_warnings = pWARN_NONE;
1131 ENTER;
1132 SAVEVPTR (PL_curcop);
1133 PL_curcop = &cop;
1134 pv_uni_display (uni, dec.cur, dec.end - dec.cur, 20, UNI_DISPLAY_QQ);
1135 LEAVE;
1136
1137 croak ("%s, at character offset %d [\"%s\"]",
1138 dec.err,
1139 (int)offset,
1140 dec.cur != dec.end ? SvPV_nolen (uni) : "(end of string)");
1141 }
1142
1143 sv = sv_2mortal (sv);
1144
1145 if (!(dec.flags & F_ALLOW_NONREF) && !SvROK (sv))
1146 croak ("JSON text must be an object or array (but found number, string, true, false or null, use allow_nonref to allow this)");
1147
1148 return sv;
1149 }
1150
1151 /////////////////////////////////////////////////////////////////////////////
1152 // XS interface functions
1153
1154 MODULE = JSON::XS PACKAGE = JSON::XS
1155
1156 BOOT:
1157 {
1158 int i;
1159
1160 for (i = 0; i < 256; ++i)
1161 decode_hexdigit [i] =
1162 i >= '0' && i <= '9' ? i - '0'
1163 : i >= 'a' && i <= 'f' ? i - 'a' + 10
1164 : i >= 'A' && i <= 'F' ? i - 'A' + 10
1165 : -1;
1166
1167 json_stash = gv_stashpv ("JSON::XS", 1);
1168 }
1169
1170 PROTOTYPES: DISABLE
1171
1172 SV *new (char *dummy)
1173 CODE:
1174 RETVAL = sv_bless (newRV_noinc (newSVuv (F_DEFAULT)), json_stash);
1175 OUTPUT:
1176 RETVAL
1177
1178 SV *ascii (SV *self, int enable = 1)
1179 ALIAS:
1180 ascii = F_ASCII
1181 latin1 = F_LATIN1
1182 utf8 = F_UTF8
1183 indent = F_INDENT
1184 canonical = F_CANONICAL
1185 space_before = F_SPACE_BEFORE
1186 space_after = F_SPACE_AFTER
1187 pretty = F_PRETTY
1188 allow_nonref = F_ALLOW_NONREF
1189 shrink = F_SHRINK
1190 CODE:
1191 {
1192 UV *uv = SvJSON (self);
1193 if (enable)
1194 *uv |= ix;
1195 else
1196 *uv &= ~ix;
1197
1198 RETVAL = newSVsv (self);
1199 }
1200 OUTPUT:
1201 RETVAL
1202
1203 SV *max_depth (SV *self, UV max_depth = 0x80000000UL)
1204 CODE:
1205 {
1206 UV *uv = SvJSON (self);
1207 UV log2 = 0;
1208
1209 if (max_depth > 0x80000000UL) max_depth = 0x80000000UL;
1210
1211 while ((1UL << log2) < max_depth)
1212 ++log2;
1213
1214 *uv = *uv & ~F_MAXDEPTH | (log2 << S_MAXDEPTH);
1215
1216 RETVAL = newSVsv (self);
1217 }
1218 OUTPUT:
1219 RETVAL
1220
1221 void encode (SV *self, SV *scalar)
1222 PPCODE:
1223 XPUSHs (encode_json (scalar, *SvJSON (self)));
1224
1225 void decode (SV *self, SV *jsonstr)
1226 PPCODE:
1227 XPUSHs (decode_json (jsonstr, *SvJSON (self), 0));
1228
1229 void decode_prefix (SV *self, SV *jsonstr)
1230 PPCODE:
1231 {
1232 UV offset;
1233 EXTEND (SP, 2);
1234 PUSHs (decode_json (jsonstr, *SvJSON (self), &offset));
1235 PUSHs (sv_2mortal (newSVuv (offset)));
1236 }
1237
1238 PROTOTYPES: ENABLE
1239
1240 void to_json (SV *scalar)
1241 ALIAS:
1242 objToJson = 0
1243 PPCODE:
1244 XPUSHs (encode_json (scalar, F_DEFAULT | F_UTF8));
1245
1246 void from_json (SV *jsonstr)
1247 ALIAS:
1248 jsonToObj = 0
1249 PPCODE:
1250 XPUSHs (decode_json (jsonstr, F_DEFAULT | F_UTF8, 0));
1251