ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/JSON-XS/XS.xs
Revision: 1.43
Committed: Sat Jun 23 23:49:29 2007 UTC (16 years, 10 months ago) by root
Branch: MAIN
CVS Tags: rel-1_3
Changes since 1.42: +6 -2 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. if it breaks, you get to keep the pieces.
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 static SV *json_true, *json_false;
61
62 /////////////////////////////////////////////////////////////////////////////
63 // utility functions
64
65 static UV *
66 SvJSON (SV *sv)
67 {
68 if (!(SvROK (sv) && SvOBJECT (SvRV (sv)) && SvSTASH (SvRV (sv)) == json_stash))
69 croak ("object is not of type JSON::XS");
70
71 return &SvUVX (SvRV (sv));
72 }
73
74 static void
75 shrink (SV *sv)
76 {
77 sv_utf8_downgrade (sv, 1);
78 if (SvLEN (sv) > SvCUR (sv) + 1)
79 {
80 #ifdef SvPV_shrink_to_cur
81 SvPV_shrink_to_cur (sv);
82 #elif defined (SvPV_renew)
83 SvPV_renew (sv, SvCUR (sv) + 1);
84 #endif
85 }
86 }
87
88 // decode an utf-8 character and return it, or (UV)-1 in
89 // case of an error.
90 // we special-case "safe" characters from U+80 .. U+7FF,
91 // but use the very good perl function to parse anything else.
92 // note that we never call this function for a ascii codepoints
93 inline UV
94 decode_utf8 (unsigned char *s, STRLEN len, STRLEN *clen)
95 {
96 if (expect_false (s[0] > 0xdf || s[0] < 0xc2))
97 return utf8n_to_uvuni (s, len, clen, UTF8_CHECK_ONLY);
98 else if (len > 1 && s[1] >= 0x80 && s[1] <= 0xbf)
99 {
100 *clen = 2;
101 return ((s[0] & 0x1f) << 6) | (s[1] & 0x3f);
102 }
103 else
104 {
105 *clen = (STRLEN)-1;
106 return (UV)-1;
107 }
108 }
109
110 /////////////////////////////////////////////////////////////////////////////
111 // encoder
112
113 // structure used for encoding JSON
114 typedef struct
115 {
116 char *cur; // SvPVX (sv) + current output position
117 char *end; // SvEND (sv)
118 SV *sv; // result scalar
119 U32 flags; // F_*
120 U32 indent; // indentation level
121 U32 maxdepth; // max. indentation/recursion level
122 } enc_t;
123
124 inline void
125 need (enc_t *enc, STRLEN len)
126 {
127 if (expect_false (enc->cur + len >= enc->end))
128 {
129 STRLEN cur = enc->cur - SvPVX (enc->sv);
130 SvGROW (enc->sv, cur + len + 1);
131 enc->cur = SvPVX (enc->sv) + cur;
132 enc->end = SvPVX (enc->sv) + SvLEN (enc->sv) - 1;
133 }
134 }
135
136 inline void
137 encode_ch (enc_t *enc, char ch)
138 {
139 need (enc, 1);
140 *enc->cur++ = ch;
141 }
142
143 static void
144 encode_str (enc_t *enc, char *str, STRLEN len, int is_utf8)
145 {
146 char *end = str + len;
147
148 need (enc, len);
149
150 while (str < end)
151 {
152 unsigned char ch = *(unsigned char *)str;
153
154 if (expect_true (ch >= 0x20 && ch < 0x80)) // most common case
155 {
156 if (expect_false (ch == '"')) // but with slow exceptions
157 {
158 need (enc, len += 1);
159 *enc->cur++ = '\\';
160 *enc->cur++ = '"';
161 }
162 else if (expect_false (ch == '\\'))
163 {
164 need (enc, len += 1);
165 *enc->cur++ = '\\';
166 *enc->cur++ = '\\';
167 }
168 else
169 *enc->cur++ = ch;
170
171 ++str;
172 }
173 else
174 {
175 switch (ch)
176 {
177 case '\010': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'b'; ++str; break;
178 case '\011': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 't'; ++str; break;
179 case '\012': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'n'; ++str; break;
180 case '\014': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'f'; ++str; break;
181 case '\015': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'r'; ++str; break;
182
183 default:
184 {
185 STRLEN clen;
186 UV uch;
187
188 if (is_utf8)
189 {
190 uch = decode_utf8 (str, end - str, &clen);
191 if (clen == (STRLEN)-1)
192 croak ("malformed or illegal unicode character in string [%.11s], cannot convert to JSON", str);
193 }
194 else
195 {
196 uch = ch;
197 clen = 1;
198 }
199
200 if (uch > 0x10FFFFUL)
201 croak ("out of range codepoint (0x%lx) encountered, unrepresentable in JSON", (unsigned long)uch);
202
203 if (uch < 0x80 || enc->flags & F_ASCII || (enc->flags & F_LATIN1 && uch > 0xFF))
204 {
205 if (uch > 0xFFFFUL)
206 {
207 need (enc, len += 11);
208 sprintf (enc->cur, "\\u%04x\\u%04x",
209 (int)((uch - 0x10000) / 0x400 + 0xD800),
210 (int)((uch - 0x10000) % 0x400 + 0xDC00));
211 enc->cur += 12;
212 }
213 else
214 {
215 static char hexdigit [16] = "0123456789abcdef";
216 need (enc, len += 5);
217 *enc->cur++ = '\\';
218 *enc->cur++ = 'u';
219 *enc->cur++ = hexdigit [ uch >> 12 ];
220 *enc->cur++ = hexdigit [(uch >> 8) & 15];
221 *enc->cur++ = hexdigit [(uch >> 4) & 15];
222 *enc->cur++ = hexdigit [(uch >> 0) & 15];
223 }
224
225 str += clen;
226 }
227 else if (enc->flags & F_LATIN1)
228 {
229 *enc->cur++ = uch;
230 str += clen;
231 }
232 else if (is_utf8)
233 {
234 need (enc, len += clen);
235 do
236 {
237 *enc->cur++ = *str++;
238 }
239 while (--clen);
240 }
241 else
242 {
243 need (enc, len += UTF8_MAXBYTES - 1); // never more than 11 bytes needed
244 enc->cur = uvuni_to_utf8_flags (enc->cur, uch, 0);
245 ++str;
246 }
247 }
248 }
249 }
250
251 --len;
252 }
253 }
254
255 inline void
256 encode_indent (enc_t *enc)
257 {
258 if (enc->flags & F_INDENT)
259 {
260 int spaces = enc->indent * INDENT_STEP;
261
262 need (enc, spaces);
263 memset (enc->cur, ' ', spaces);
264 enc->cur += spaces;
265 }
266 }
267
268 inline void
269 encode_space (enc_t *enc)
270 {
271 need (enc, 1);
272 encode_ch (enc, ' ');
273 }
274
275 inline void
276 encode_nl (enc_t *enc)
277 {
278 if (enc->flags & F_INDENT)
279 {
280 need (enc, 1);
281 encode_ch (enc, '\n');
282 }
283 }
284
285 inline void
286 encode_comma (enc_t *enc)
287 {
288 encode_ch (enc, ',');
289
290 if (enc->flags & F_INDENT)
291 encode_nl (enc);
292 else if (enc->flags & F_SPACE_AFTER)
293 encode_space (enc);
294 }
295
296 static void encode_sv (enc_t *enc, SV *sv);
297
298 static void
299 encode_av (enc_t *enc, AV *av)
300 {
301 int i, len = av_len (av);
302
303 if (enc->indent >= enc->maxdepth)
304 croak ("data structure too deep (hit recursion limit)");
305
306 encode_ch (enc, '['); encode_nl (enc);
307 ++enc->indent;
308
309 for (i = 0; i <= len; ++i)
310 {
311 encode_indent (enc);
312 encode_sv (enc, *av_fetch (av, i, 0));
313
314 if (i < len)
315 encode_comma (enc);
316 }
317
318 encode_nl (enc);
319
320 --enc->indent;
321 encode_indent (enc); encode_ch (enc, ']');
322 }
323
324 static void
325 encode_he (enc_t *enc, HE *he)
326 {
327 encode_ch (enc, '"');
328
329 if (HeKLEN (he) == HEf_SVKEY)
330 {
331 SV *sv = HeSVKEY (he);
332 STRLEN len;
333 char *str;
334
335 SvGETMAGIC (sv);
336 str = SvPV (sv, len);
337
338 encode_str (enc, str, len, SvUTF8 (sv));
339 }
340 else
341 encode_str (enc, HeKEY (he), HeKLEN (he), HeKUTF8 (he));
342
343 encode_ch (enc, '"');
344
345 if (enc->flags & F_SPACE_BEFORE) encode_space (enc);
346 encode_ch (enc, ':');
347 if (enc->flags & F_SPACE_AFTER ) encode_space (enc);
348 encode_sv (enc, HeVAL (he));
349 }
350
351 // compare hash entries, used when all keys are bytestrings
352 static int
353 he_cmp_fast (const void *a_, const void *b_)
354 {
355 int cmp;
356
357 HE *a = *(HE **)a_;
358 HE *b = *(HE **)b_;
359
360 STRLEN la = HeKLEN (a);
361 STRLEN lb = HeKLEN (b);
362
363 if (!(cmp = memcmp (HeKEY (a), HeKEY (b), la < lb ? la : lb)))
364 cmp = la - lb;
365
366 return cmp;
367 }
368
369 // compare hash entries, used when some keys are sv's or utf-x
370 static int
371 he_cmp_slow (const void *a, const void *b)
372 {
373 return sv_cmp (HeSVKEY_force (*(HE **)a), HeSVKEY_force (*(HE **)b));
374 }
375
376 static void
377 encode_hv (enc_t *enc, HV *hv)
378 {
379 int count, i;
380
381 if (enc->indent >= enc->maxdepth)
382 croak ("data structure too deep (hit recursion limit)");
383
384 encode_ch (enc, '{'); encode_nl (enc); ++enc->indent;
385
386 if ((count = hv_iterinit (hv)))
387 {
388 // for canonical output we have to sort by keys first
389 // actually, this is mostly due to the stupid so-called
390 // security workaround added somewhere in 5.8.x.
391 // that randomises hash orderings
392 if (enc->flags & F_CANONICAL)
393 {
394 int fast = 1;
395 HE *he;
396 #if defined(__BORLANDC__) || defined(_MSC_VER)
397 HE **hes = _alloca (count * sizeof (HE));
398 #else
399 HE *hes [count]; // if your compiler dies here, you need to enable C99 mode
400 #endif
401
402 i = 0;
403 while ((he = hv_iternext (hv)))
404 {
405 hes [i++] = he;
406 if (HeKLEN (he) < 0 || HeKUTF8 (he))
407 fast = 0;
408 }
409
410 assert (i == count);
411
412 if (fast)
413 qsort (hes, count, sizeof (HE *), he_cmp_fast);
414 else
415 {
416 // hack to forcefully disable "use bytes"
417 COP cop = *PL_curcop;
418 cop.op_private = 0;
419
420 ENTER;
421 SAVETMPS;
422
423 SAVEVPTR (PL_curcop);
424 PL_curcop = &cop;
425
426 qsort (hes, count, sizeof (HE *), he_cmp_slow);
427
428 FREETMPS;
429 LEAVE;
430 }
431
432 for (i = 0; i < count; ++i)
433 {
434 encode_indent (enc);
435 encode_he (enc, hes [i]);
436
437 if (i < count - 1)
438 encode_comma (enc);
439 }
440
441 encode_nl (enc);
442 }
443 else
444 {
445 HE *he = hv_iternext (hv);
446
447 for (;;)
448 {
449 encode_indent (enc);
450 encode_he (enc, he);
451
452 if (!(he = hv_iternext (hv)))
453 break;
454
455 encode_comma (enc);
456 }
457
458 encode_nl (enc);
459 }
460 }
461
462 --enc->indent; encode_indent (enc); encode_ch (enc, '}');
463 }
464
465 // encode objects, arrays and special \0=false and \1=true values.
466 static void
467 encode_rv (enc_t *enc, SV *sv)
468 {
469 svtype svt;
470
471 SvGETMAGIC (sv);
472 svt = SvTYPE (sv);
473
474 if (svt == SVt_PVHV)
475 encode_hv (enc, (HV *)sv);
476 else if (svt == SVt_PVAV)
477 encode_av (enc, (AV *)sv);
478 else if (svt < SVt_PVAV)
479 {
480 if (SvNIOK (sv) && SvIV (sv) == 0)
481 encode_str (enc, "false", 5, 0);
482 else if (SvNIOK (sv) && SvIV (sv) == 1)
483 encode_str (enc, "true", 4, 0);
484 else
485 croak ("cannot encode reference to scalar '%s' unless the scalar is 0 or 1",
486 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
487 }
488 else
489 croak ("encountered %s, but JSON can only represent references to arrays or hashes",
490 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
491 }
492
493 static void
494 encode_sv (enc_t *enc, SV *sv)
495 {
496 SvGETMAGIC (sv);
497
498 if (SvPOKp (sv))
499 {
500 STRLEN len;
501 char *str = SvPV (sv, len);
502 encode_ch (enc, '"');
503 encode_str (enc, str, len, SvUTF8 (sv));
504 encode_ch (enc, '"');
505 }
506 else if (SvNOKp (sv))
507 {
508 // trust that perl will do the right thing w.r.t. JSON syntax.
509 need (enc, NV_DIG + 32);
510 Gconvert (SvNVX (sv), NV_DIG, 0, enc->cur);
511 enc->cur += strlen (enc->cur);
512 }
513 else if (SvIOKp (sv))
514 {
515 // we assume we can always read an IV as a UV
516 if (SvUV (sv) & ~(UV)0x7fff)
517 {
518 // large integer, use the (rather slow) snprintf way.
519 need (enc, sizeof (UV) * 3);
520 enc->cur +=
521 SvIsUV(sv)
522 ? snprintf (enc->cur, sizeof (UV) * 3, "%"UVuf, (UV)SvUVX (sv))
523 : snprintf (enc->cur, sizeof (UV) * 3, "%"IVdf, (IV)SvIVX (sv));
524 }
525 else
526 {
527 // optimise the "small number case"
528 // code will likely be branchless and use only a single multiplication
529 I32 i = SvIV (sv);
530 U32 u;
531 char digit, nz = 0;
532
533 need (enc, 6);
534
535 *enc->cur = '-'; enc->cur += i < 0 ? 1 : 0;
536 u = i < 0 ? -i : i;
537
538 // convert to 4.28 fixed-point representation
539 u = u * ((0xfffffff + 10000) / 10000); // 10**5, 5 fractional digits
540
541 // now output digit by digit, each time masking out the integer part
542 // and multiplying by 5 while moving the decimal point one to the right,
543 // resulting in a net multiplication by 10.
544 // we always write the digit to memory but conditionally increment
545 // the pointer, to ease the usage of conditional move instructions.
546 digit = u >> 28; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0xfffffff) * 5;
547 digit = u >> 27; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x7ffffff) * 5;
548 digit = u >> 26; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x3ffffff) * 5;
549 digit = u >> 25; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x1ffffff) * 5;
550 digit = u >> 24; *enc->cur = digit + '0'; enc->cur += 1; // correctly generate '0'
551 }
552 }
553 else if (SvROK (sv))
554 encode_rv (enc, SvRV (sv));
555 else if (!SvOK (sv))
556 encode_str (enc, "null", 4, 0);
557 else
558 croak ("encountered perl type (%s,0x%x) that JSON cannot handle, you might want to report this",
559 SvPV_nolen (sv), SvFLAGS (sv));
560 }
561
562 static SV *
563 encode_json (SV *scalar, U32 flags)
564 {
565 enc_t enc;
566
567 if (!(flags & F_ALLOW_NONREF) && !SvROK (scalar))
568 croak ("hash- or arrayref expected (not a simple scalar, use allow_nonref to allow this)");
569
570 enc.flags = flags;
571 enc.sv = sv_2mortal (NEWSV (0, INIT_SIZE));
572 enc.cur = SvPVX (enc.sv);
573 enc.end = SvEND (enc.sv);
574 enc.indent = 0;
575 enc.maxdepth = DEC_DEPTH (flags);
576
577 SvPOK_only (enc.sv);
578 encode_sv (&enc, scalar);
579
580 SvCUR_set (enc.sv, enc.cur - SvPVX (enc.sv));
581 *SvEND (enc.sv) = 0; // many xs functions expect a trailing 0 for text strings
582
583 if (!(flags & (F_ASCII | F_LATIN1 | F_UTF8)))
584 SvUTF8_on (enc.sv);
585
586 if (enc.flags & F_SHRINK)
587 shrink (enc.sv);
588
589 return enc.sv;
590 }
591
592 /////////////////////////////////////////////////////////////////////////////
593 // decoder
594
595 // structure used for decoding JSON
596 typedef struct
597 {
598 char *cur; // current parser pointer
599 char *end; // end of input string
600 const char *err; // parse error, if != 0
601 U32 flags; // F_*
602 U32 depth; // recursion depth
603 U32 maxdepth; // recursion depth limit
604 } dec_t;
605
606 inline void
607 decode_ws (dec_t *dec)
608 {
609 for (;;)
610 {
611 char ch = *dec->cur;
612
613 if (ch > 0x20
614 || (ch != 0x20 && ch != 0x0a && ch != 0x0d && ch != 0x09))
615 break;
616
617 ++dec->cur;
618 }
619 }
620
621 #define ERR(reason) SB dec->err = reason; goto fail; SE
622
623 #define EXPECT_CH(ch) SB \
624 if (*dec->cur != ch) \
625 ERR (# ch " expected"); \
626 ++dec->cur; \
627 SE
628
629 #define DEC_INC_DEPTH if (++dec->depth > dec->maxdepth) ERR ("json datastructure exceeds maximum nesting level (set a higher max_depth)")
630 #define DEC_DEC_DEPTH --dec->depth
631
632 static SV *decode_sv (dec_t *dec);
633
634 static signed char decode_hexdigit[256];
635
636 static UV
637 decode_4hex (dec_t *dec)
638 {
639 signed char d1, d2, d3, d4;
640 unsigned char *cur = (unsigned char *)dec->cur;
641
642 d1 = decode_hexdigit [cur [0]]; if (expect_false (d1 < 0)) ERR ("exactly four hexadecimal digits expected");
643 d2 = decode_hexdigit [cur [1]]; if (expect_false (d2 < 0)) ERR ("exactly four hexadecimal digits expected");
644 d3 = decode_hexdigit [cur [2]]; if (expect_false (d3 < 0)) ERR ("exactly four hexadecimal digits expected");
645 d4 = decode_hexdigit [cur [3]]; if (expect_false (d4 < 0)) ERR ("exactly four hexadecimal digits expected");
646
647 dec->cur += 4;
648
649 return ((UV)d1) << 12
650 | ((UV)d2) << 8
651 | ((UV)d3) << 4
652 | ((UV)d4);
653
654 fail:
655 return (UV)-1;
656 }
657
658 static SV *
659 decode_str (dec_t *dec)
660 {
661 SV *sv = 0;
662 int utf8 = 0;
663 char *dec_cur = dec->cur;
664
665 do
666 {
667 char buf [SHORT_STRING_LEN + UTF8_MAXBYTES];
668 char *cur = buf;
669
670 do
671 {
672 unsigned char ch = *(unsigned char *)dec_cur++;
673
674 if (expect_false (ch == '"'))
675 {
676 --dec_cur;
677 break;
678 }
679 else if (expect_false (ch == '\\'))
680 {
681 switch (*dec_cur)
682 {
683 case '\\':
684 case '/':
685 case '"': *cur++ = *dec_cur++; break;
686
687 case 'b': ++dec_cur; *cur++ = '\010'; break;
688 case 't': ++dec_cur; *cur++ = '\011'; break;
689 case 'n': ++dec_cur; *cur++ = '\012'; break;
690 case 'f': ++dec_cur; *cur++ = '\014'; break;
691 case 'r': ++dec_cur; *cur++ = '\015'; break;
692
693 case 'u':
694 {
695 UV lo, hi;
696 ++dec_cur;
697
698 dec->cur = dec_cur;
699 hi = decode_4hex (dec);
700 dec_cur = dec->cur;
701 if (hi == (UV)-1)
702 goto fail;
703
704 // possibly a surrogate pair
705 if (hi >= 0xd800)
706 if (hi < 0xdc00)
707 {
708 if (dec_cur [0] != '\\' || dec_cur [1] != 'u')
709 ERR ("missing low surrogate character in surrogate pair");
710
711 dec_cur += 2;
712
713 dec->cur = dec_cur;
714 lo = decode_4hex (dec);
715 dec_cur = dec->cur;
716 if (lo == (UV)-1)
717 goto fail;
718
719 if (lo < 0xdc00 || lo >= 0xe000)
720 ERR ("surrogate pair expected");
721
722 hi = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000;
723 }
724 else if (hi < 0xe000)
725 ERR ("missing high surrogate character in surrogate pair");
726
727 if (hi >= 0x80)
728 {
729 utf8 = 1;
730
731 cur = (char *)uvuni_to_utf8_flags (cur, hi, 0);
732 }
733 else
734 *cur++ = hi;
735 }
736 break;
737
738 default:
739 --dec_cur;
740 ERR ("illegal backslash escape sequence in string");
741 }
742 }
743 else if (expect_true (ch >= 0x20 && ch <= 0x7f))
744 *cur++ = ch;
745 else if (ch >= 0x80)
746 {
747 STRLEN clen;
748 UV uch;
749
750 --dec_cur;
751
752 uch = decode_utf8 (dec_cur, dec->end - dec_cur, &clen);
753 if (clen == (STRLEN)-1)
754 ERR ("malformed UTF-8 character in JSON string");
755
756 do
757 *cur++ = *dec_cur++;
758 while (--clen);
759
760 utf8 = 1;
761 }
762 else
763 {
764 --dec_cur;
765
766 if (!ch)
767 ERR ("unexpected end of string while parsing JSON string");
768 else
769 ERR ("invalid character encountered while parsing JSON string");
770 }
771 }
772 while (cur < buf + SHORT_STRING_LEN);
773
774 {
775 STRLEN len = cur - buf;
776
777 if (sv)
778 {
779 SvGROW (sv, SvCUR (sv) + len + 1);
780 memcpy (SvPVX (sv) + SvCUR (sv), buf, len);
781 SvCUR_set (sv, SvCUR (sv) + len);
782 }
783 else
784 sv = newSVpvn (buf, len);
785 }
786 }
787 while (*dec_cur != '"');
788
789 ++dec_cur;
790
791 if (sv)
792 {
793 SvPOK_only (sv);
794 *SvEND (sv) = 0;
795
796 if (utf8)
797 SvUTF8_on (sv);
798 }
799 else
800 sv = newSVpvn ("", 0);
801
802 dec->cur = dec_cur;
803 return sv;
804
805 fail:
806 dec->cur = dec_cur;
807 return 0;
808 }
809
810 static SV *
811 decode_num (dec_t *dec)
812 {
813 int is_nv = 0;
814 char *start = dec->cur;
815
816 // [minus]
817 if (*dec->cur == '-')
818 ++dec->cur;
819
820 if (*dec->cur == '0')
821 {
822 ++dec->cur;
823 if (*dec->cur >= '0' && *dec->cur <= '9')
824 ERR ("malformed number (leading zero must not be followed by another digit)");
825 }
826 else if (*dec->cur < '0' || *dec->cur > '9')
827 ERR ("malformed number (no digits after initial minus)");
828 else
829 do
830 {
831 ++dec->cur;
832 }
833 while (*dec->cur >= '0' && *dec->cur <= '9');
834
835 // [frac]
836 if (*dec->cur == '.')
837 {
838 ++dec->cur;
839
840 if (*dec->cur < '0' || *dec->cur > '9')
841 ERR ("malformed number (no digits after decimal point)");
842
843 do
844 {
845 ++dec->cur;
846 }
847 while (*dec->cur >= '0' && *dec->cur <= '9');
848
849 is_nv = 1;
850 }
851
852 // [exp]
853 if (*dec->cur == 'e' || *dec->cur == 'E')
854 {
855 ++dec->cur;
856
857 if (*dec->cur == '-' || *dec->cur == '+')
858 ++dec->cur;
859
860 if (*dec->cur < '0' || *dec->cur > '9')
861 ERR ("malformed number (no digits after exp sign)");
862
863 do
864 {
865 ++dec->cur;
866 }
867 while (*dec->cur >= '0' && *dec->cur <= '9');
868
869 is_nv = 1;
870 }
871
872 if (!is_nv)
873 {
874 // special case the rather common 1..4-digit-int case, assumes 32 bit ints or so
875 if (*start == '-')
876 switch (dec->cur - start)
877 {
878 case 2: return newSViv (-( start [1] - '0' * 1));
879 case 3: return newSViv (-( start [1] * 10 + start [2] - '0' * 11));
880 case 4: return newSViv (-( start [1] * 100 + start [2] * 10 + start [3] - '0' * 111));
881 case 5: return newSViv (-(start [1] * 1000 + start [2] * 100 + start [3] * 10 + start [4] - '0' * 1111));
882 }
883 else
884 switch (dec->cur - start)
885 {
886 case 1: return newSViv ( start [0] - '0' * 1);
887 case 2: return newSViv ( start [0] * 10 + start [1] - '0' * 11);
888 case 3: return newSViv ( start [0] * 100 + start [1] * 10 + start [2] - '0' * 111);
889 case 4: return newSViv ( start [0] * 1000 + start [1] * 100 + start [2] * 10 + start [3] - '0' * 1111);
890 }
891
892 {
893 UV uv;
894 int numtype = grok_number (start, dec->cur - start, &uv);
895 if (numtype & IS_NUMBER_IN_UV)
896 if (numtype & IS_NUMBER_NEG)
897 {
898 if (uv < (UV)IV_MIN)
899 return newSViv (-(IV)uv);
900 }
901 else
902 return newSVuv (uv);
903
904 // here would likely be the place for bigint support
905 }
906 }
907
908 // if we ever support bigint or bigfloat, this is the place for bigfloat
909 return newSVnv (Atof (start));
910
911 fail:
912 return 0;
913 }
914
915 static SV *
916 decode_av (dec_t *dec)
917 {
918 AV *av = newAV ();
919
920 DEC_INC_DEPTH;
921 decode_ws (dec);
922
923 if (*dec->cur == ']')
924 ++dec->cur;
925 else
926 for (;;)
927 {
928 SV *value;
929
930 value = decode_sv (dec);
931 if (!value)
932 goto fail;
933
934 av_push (av, value);
935
936 decode_ws (dec);
937
938 if (*dec->cur == ']')
939 {
940 ++dec->cur;
941 break;
942 }
943
944 if (*dec->cur != ',')
945 ERR (", or ] expected while parsing array");
946
947 ++dec->cur;
948 }
949
950 DEC_DEC_DEPTH;
951 return newRV_noinc ((SV *)av);
952
953 fail:
954 SvREFCNT_dec (av);
955 DEC_DEC_DEPTH;
956 return 0;
957 }
958
959 static SV *
960 decode_hv (dec_t *dec)
961 {
962 HV *hv = newHV ();
963
964 DEC_INC_DEPTH;
965 decode_ws (dec);
966
967 if (*dec->cur == '}')
968 ++dec->cur;
969 else
970 for (;;)
971 {
972 SV *key, *value;
973
974 decode_ws (dec); EXPECT_CH ('"');
975
976 key = decode_str (dec);
977 if (!key)
978 goto fail;
979
980 decode_ws (dec); EXPECT_CH (':');
981
982 value = decode_sv (dec);
983 if (!value)
984 {
985 SvREFCNT_dec (key);
986 goto fail;
987 }
988
989 hv_store_ent (hv, key, value, 0);
990 SvREFCNT_dec (key);
991
992 decode_ws (dec);
993
994 if (*dec->cur == '}')
995 {
996 ++dec->cur;
997 break;
998 }
999
1000 if (*dec->cur != ',')
1001 ERR (", or } expected while parsing object/hash");
1002
1003 ++dec->cur;
1004 }
1005
1006 DEC_DEC_DEPTH;
1007 return newRV_noinc ((SV *)hv);
1008
1009 fail:
1010 SvREFCNT_dec (hv);
1011 DEC_DEC_DEPTH;
1012 return 0;
1013 }
1014
1015 static SV *
1016 decode_sv (dec_t *dec)
1017 {
1018 decode_ws (dec);
1019
1020 // the beauty of JSON: you need exactly one character lookahead
1021 // to parse anything.
1022 switch (*dec->cur)
1023 {
1024 case '"': ++dec->cur; return decode_str (dec);
1025 case '[': ++dec->cur; return decode_av (dec);
1026 case '{': ++dec->cur; return decode_hv (dec);
1027
1028 case '-':
1029 case '0': case '1': case '2': case '3': case '4':
1030 case '5': case '6': case '7': case '8': case '9':
1031 return decode_num (dec);
1032
1033 case 't':
1034 if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "true", 4))
1035 {
1036 dec->cur += 4;
1037 return SvREFCNT_inc (json_true);
1038 }
1039 else
1040 ERR ("'true' expected");
1041
1042 break;
1043
1044 case 'f':
1045 if (dec->end - dec->cur >= 5 && !memcmp (dec->cur, "false", 5))
1046 {
1047 dec->cur += 5;
1048 return SvREFCNT_inc (json_false);
1049 }
1050 else
1051 ERR ("'false' expected");
1052
1053 break;
1054
1055 case 'n':
1056 if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "null", 4))
1057 {
1058 dec->cur += 4;
1059 return newSVsv (&PL_sv_undef);
1060 }
1061 else
1062 ERR ("'null' expected");
1063
1064 break;
1065
1066 default:
1067 ERR ("malformed JSON string, neither array, object, number, string or atom");
1068 break;
1069 }
1070
1071 fail:
1072 return 0;
1073 }
1074
1075 static SV *
1076 decode_json (SV *string, U32 flags, UV *offset_return)
1077 {
1078 dec_t dec;
1079 UV offset;
1080 SV *sv;
1081
1082 SvGETMAGIC (string);
1083 SvUPGRADE (string, SVt_PV);
1084
1085 if (flags & F_UTF8)
1086 sv_utf8_downgrade (string, 0);
1087 else
1088 sv_utf8_upgrade (string);
1089
1090 SvGROW (string, SvCUR (string) + 1); // should basically be a NOP
1091
1092 dec.flags = flags;
1093 dec.cur = SvPVX (string);
1094 dec.end = SvEND (string);
1095 dec.err = 0;
1096 dec.depth = 0;
1097 dec.maxdepth = DEC_DEPTH (dec.flags);
1098
1099 *dec.end = 0; // this should basically be a nop, too, but make sure it's there
1100 sv = decode_sv (&dec);
1101
1102 if (!(offset_return || !sv))
1103 {
1104 // check for trailing garbage
1105 decode_ws (&dec);
1106
1107 if (*dec.cur)
1108 {
1109 dec.err = "garbage after JSON object";
1110 SvREFCNT_dec (sv);
1111 sv = 0;
1112 }
1113 }
1114
1115 if (offset_return || !sv)
1116 {
1117 offset = dec.flags & F_UTF8
1118 ? dec.cur - SvPVX (string)
1119 : utf8_distance (dec.cur, SvPVX (string));
1120
1121 if (offset_return)
1122 *offset_return = offset;
1123 }
1124
1125 if (!sv)
1126 {
1127 SV *uni = sv_newmortal ();
1128
1129 // horrible hack to silence warning inside pv_uni_display
1130 COP cop = *PL_curcop;
1131 cop.cop_warnings = pWARN_NONE;
1132 ENTER;
1133 SAVEVPTR (PL_curcop);
1134 PL_curcop = &cop;
1135 pv_uni_display (uni, dec.cur, dec.end - dec.cur, 20, UNI_DISPLAY_QQ);
1136 LEAVE;
1137
1138 croak ("%s, at character offset %d [\"%s\"]",
1139 dec.err,
1140 (int)offset,
1141 dec.cur != dec.end ? SvPV_nolen (uni) : "(end of string)");
1142 }
1143
1144 sv = sv_2mortal (sv);
1145
1146 if (!(dec.flags & F_ALLOW_NONREF) && !SvROK (sv))
1147 croak ("JSON text must be an object or array (but found number, string, true, false or null, use allow_nonref to allow this)");
1148
1149 return sv;
1150 }
1151
1152 /////////////////////////////////////////////////////////////////////////////
1153 // XS interface functions
1154
1155 MODULE = JSON::XS PACKAGE = JSON::XS
1156
1157 BOOT:
1158 {
1159 int i;
1160
1161 for (i = 0; i < 256; ++i)
1162 decode_hexdigit [i] =
1163 i >= '0' && i <= '9' ? i - '0'
1164 : i >= 'a' && i <= 'f' ? i - 'a' + 10
1165 : i >= 'A' && i <= 'F' ? i - 'A' + 10
1166 : -1;
1167
1168 json_stash = gv_stashpv ("JSON::XS", 1);
1169
1170 json_true = get_sv ("JSON::XS::true" , 1); SvREADONLY_on (json_true );
1171 json_false = get_sv ("JSON::XS::false", 1); SvREADONLY_on (json_false);
1172 }
1173
1174 PROTOTYPES: DISABLE
1175
1176 SV *new (char *dummy)
1177 CODE:
1178 RETVAL = sv_bless (newRV_noinc (newSVuv (F_DEFAULT)), json_stash);
1179 OUTPUT:
1180 RETVAL
1181
1182 SV *ascii (SV *self, int enable = 1)
1183 ALIAS:
1184 ascii = F_ASCII
1185 latin1 = F_LATIN1
1186 utf8 = F_UTF8
1187 indent = F_INDENT
1188 canonical = F_CANONICAL
1189 space_before = F_SPACE_BEFORE
1190 space_after = F_SPACE_AFTER
1191 pretty = F_PRETTY
1192 allow_nonref = F_ALLOW_NONREF
1193 shrink = F_SHRINK
1194 CODE:
1195 {
1196 UV *uv = SvJSON (self);
1197 if (enable)
1198 *uv |= ix;
1199 else
1200 *uv &= ~ix;
1201
1202 RETVAL = newSVsv (self);
1203 }
1204 OUTPUT:
1205 RETVAL
1206
1207 SV *max_depth (SV *self, UV max_depth = 0x80000000UL)
1208 CODE:
1209 {
1210 UV *uv = SvJSON (self);
1211 UV log2 = 0;
1212
1213 if (max_depth > 0x80000000UL) max_depth = 0x80000000UL;
1214
1215 while ((1UL << log2) < max_depth)
1216 ++log2;
1217
1218 *uv = *uv & ~F_MAXDEPTH | (log2 << S_MAXDEPTH);
1219
1220 RETVAL = newSVsv (self);
1221 }
1222 OUTPUT:
1223 RETVAL
1224
1225 void encode (SV *self, SV *scalar)
1226 PPCODE:
1227 XPUSHs (encode_json (scalar, *SvJSON (self)));
1228
1229 void decode (SV *self, SV *jsonstr)
1230 PPCODE:
1231 XPUSHs (decode_json (jsonstr, *SvJSON (self), 0));
1232
1233 void decode_prefix (SV *self, SV *jsonstr)
1234 PPCODE:
1235 {
1236 UV offset;
1237 EXTEND (SP, 2);
1238 PUSHs (decode_json (jsonstr, *SvJSON (self), &offset));
1239 PUSHs (sv_2mortal (newSVuv (offset)));
1240 }
1241
1242 PROTOTYPES: ENABLE
1243
1244 void to_json (SV *scalar)
1245 ALIAS:
1246 objToJson = 0
1247 PPCODE:
1248 XPUSHs (encode_json (scalar, F_DEFAULT | F_UTF8));
1249
1250 void from_json (SV *jsonstr)
1251 ALIAS:
1252 jsonToObj = 0
1253 PPCODE:
1254 XPUSHs (decode_json (jsonstr, F_DEFAULT | F_UTF8, 0));
1255