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/cvs/JSON-XS/XS.xs
Revision: 1.44
Committed: Mon Jun 25 04:08:17 2007 UTC (16 years, 10 months ago) by root
Branch: MAIN
Changes since 1.43: +83 -27 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_ALLOW_BLESSED 0x00000400UL
30 #define F_CONV_BLESSED 0x00000800UL // NYI
31 #define F_MAXDEPTH 0xf8000000UL
32 #define S_MAXDEPTH 27
33
34 #define DEC_DEPTH(flags) (1UL << ((flags & F_MAXDEPTH) >> S_MAXDEPTH))
35
36 #define F_PRETTY F_INDENT | F_SPACE_BEFORE | F_SPACE_AFTER
37 #define F_DEFAULT (9UL << S_MAXDEPTH)
38
39 #define INIT_SIZE 32 // initial scalar size to be allocated
40 #define INDENT_STEP 3 // spaces per indentation level
41
42 #define SHORT_STRING_LEN 16384 // special-case strings of up to this size
43
44 #define SB do {
45 #define SE } while (0)
46
47 #if __GNUC__ >= 3
48 # define expect(expr,value) __builtin_expect ((expr),(value))
49 # define inline inline
50 #else
51 # define expect(expr,value) (expr)
52 # define inline static
53 #endif
54
55 #define expect_false(expr) expect ((expr) != 0, 0)
56 #define expect_true(expr) expect ((expr) != 0, 1)
57
58 static HV *json_stash, *json_boolean_stash; // JSON::XS::
59 static SV *json_true, *json_false;
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 (expect_false (SvOBJECT (sv)))
474 {
475 if (SvSTASH (sv) == json_boolean_stash)
476 {
477 if (SvIV (sv) == 0)
478 encode_str (enc, "false", 5, 0);
479 else
480 encode_str (enc, "true", 4, 0);
481 }
482 else
483 {
484 #if 0
485 if (0 && sv_derived_from (rv, "JSON::Literal"))
486 {
487 // not yet
488 }
489 #endif
490 if (enc->flags & F_CONV_BLESSED)
491 {
492 // we re-bless the reference to get overload and other niceties right
493 GV *to_json = gv_fetchmethod_autoload (SvSTASH (sv), "TO_JSON", 1);
494
495 if (to_json)
496 {
497 dSP;
498 ENTER;
499 SAVETMPS;
500 PUSHMARK (SP);
501 XPUSHs (sv_bless (sv_2mortal (newRV_inc (sv)), SvSTASH (sv)));
502
503 // calling with G_SCALAR ensures that we always get a 1 reutrn value
504 // check anyways.
505 PUTBACK;
506 assert (1 == call_sv ((SV *)GvCV (to_json), G_SCALAR));
507 SPAGAIN;
508
509 encode_sv (enc, POPs);
510
511 FREETMPS;
512 LEAVE;
513 }
514 else if (enc->flags & F_ALLOW_BLESSED)
515 encode_str (enc, "null", 4, 0);
516 else
517 croak ("encountered object '%s', but neither allow_blessed enabled nor TO_JSON method available on it",
518 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
519 }
520 else if (enc->flags & F_ALLOW_BLESSED)
521 encode_str (enc, "null", 4, 0);
522 else
523 croak ("encountered object '%s', but neither allow_blessed nor convert_blessed settings are enabled",
524 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
525 }
526 }
527 else if (svt == SVt_PVHV)
528 encode_hv (enc, (HV *)sv);
529 else if (svt == SVt_PVAV)
530 encode_av (enc, (AV *)sv);
531 else if (svt < SVt_PVAV)
532 {
533 if (SvNIOK (sv) && SvIV (sv) == 0)
534 encode_str (enc, "false", 5, 0);
535 else if (SvNIOK (sv) && SvIV (sv) == 1)
536 encode_str (enc, "true", 4, 0);
537 else
538 croak ("cannot encode reference to scalar '%s' unless the scalar is 0 or 1",
539 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
540 }
541 else
542 croak ("encountered %s, but JSON can only represent references to arrays or hashes",
543 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
544 }
545
546 static void
547 encode_sv (enc_t *enc, SV *sv)
548 {
549 SvGETMAGIC (sv);
550
551 if (SvPOKp (sv))
552 {
553 STRLEN len;
554 char *str = SvPV (sv, len);
555 encode_ch (enc, '"');
556 encode_str (enc, str, len, SvUTF8 (sv));
557 encode_ch (enc, '"');
558 }
559 else if (SvNOKp (sv))
560 {
561 // trust that perl will do the right thing w.r.t. JSON syntax.
562 need (enc, NV_DIG + 32);
563 Gconvert (SvNVX (sv), NV_DIG, 0, enc->cur);
564 enc->cur += strlen (enc->cur);
565 }
566 else if (SvIOKp (sv))
567 {
568 // we assume we can always read an IV as a UV
569 if (SvUV (sv) & ~(UV)0x7fff)
570 {
571 // large integer, use the (rather slow) snprintf way.
572 need (enc, sizeof (UV) * 3);
573 enc->cur +=
574 SvIsUV(sv)
575 ? snprintf (enc->cur, sizeof (UV) * 3, "%"UVuf, (UV)SvUVX (sv))
576 : snprintf (enc->cur, sizeof (UV) * 3, "%"IVdf, (IV)SvIVX (sv));
577 }
578 else
579 {
580 // optimise the "small number case"
581 // code will likely be branchless and use only a single multiplication
582 I32 i = SvIV (sv);
583 U32 u;
584 char digit, nz = 0;
585
586 need (enc, 6);
587
588 *enc->cur = '-'; enc->cur += i < 0 ? 1 : 0;
589 u = i < 0 ? -i : i;
590
591 // convert to 4.28 fixed-point representation
592 u = u * ((0xfffffff + 10000) / 10000); // 10**5, 5 fractional digits
593
594 // now output digit by digit, each time masking out the integer part
595 // and multiplying by 5 while moving the decimal point one to the right,
596 // resulting in a net multiplication by 10.
597 // we always write the digit to memory but conditionally increment
598 // the pointer, to ease the usage of conditional move instructions.
599 digit = u >> 28; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0xfffffff) * 5;
600 digit = u >> 27; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x7ffffff) * 5;
601 digit = u >> 26; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x3ffffff) * 5;
602 digit = u >> 25; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x1ffffff) * 5;
603 digit = u >> 24; *enc->cur = digit + '0'; enc->cur += 1; // correctly generate '0'
604 }
605 }
606 else if (SvROK (sv))
607 encode_rv (enc, SvRV (sv));
608 else if (!SvOK (sv))
609 encode_str (enc, "null", 4, 0);
610 else
611 croak ("encountered perl type (%s,0x%x) that JSON cannot handle, you might want to report this",
612 SvPV_nolen (sv), SvFLAGS (sv));
613 }
614
615 static SV *
616 encode_json (SV *scalar, U32 flags)
617 {
618 enc_t enc;
619
620 if (!(flags & F_ALLOW_NONREF) && !SvROK (scalar))
621 croak ("hash- or arrayref expected (not a simple scalar, use allow_nonref to allow this)");
622
623 enc.flags = flags;
624 enc.sv = sv_2mortal (NEWSV (0, INIT_SIZE));
625 enc.cur = SvPVX (enc.sv);
626 enc.end = SvEND (enc.sv);
627 enc.indent = 0;
628 enc.maxdepth = DEC_DEPTH (flags);
629
630 SvPOK_only (enc.sv);
631 encode_sv (&enc, scalar);
632
633 SvCUR_set (enc.sv, enc.cur - SvPVX (enc.sv));
634 *SvEND (enc.sv) = 0; // many xs functions expect a trailing 0 for text strings
635
636 if (!(flags & (F_ASCII | F_LATIN1 | F_UTF8)))
637 SvUTF8_on (enc.sv);
638
639 if (enc.flags & F_SHRINK)
640 shrink (enc.sv);
641
642 return enc.sv;
643 }
644
645 /////////////////////////////////////////////////////////////////////////////
646 // decoder
647
648 // structure used for decoding JSON
649 typedef struct
650 {
651 char *cur; // current parser pointer
652 char *end; // end of input string
653 const char *err; // parse error, if != 0
654 U32 flags; // F_*
655 U32 depth; // recursion depth
656 U32 maxdepth; // recursion depth limit
657 } dec_t;
658
659 inline void
660 decode_ws (dec_t *dec)
661 {
662 for (;;)
663 {
664 char ch = *dec->cur;
665
666 if (ch > 0x20
667 || (ch != 0x20 && ch != 0x0a && ch != 0x0d && ch != 0x09))
668 break;
669
670 ++dec->cur;
671 }
672 }
673
674 #define ERR(reason) SB dec->err = reason; goto fail; SE
675
676 #define EXPECT_CH(ch) SB \
677 if (*dec->cur != ch) \
678 ERR (# ch " expected"); \
679 ++dec->cur; \
680 SE
681
682 #define DEC_INC_DEPTH if (++dec->depth > dec->maxdepth) ERR ("json datastructure exceeds maximum nesting level (set a higher max_depth)")
683 #define DEC_DEC_DEPTH --dec->depth
684
685 static SV *decode_sv (dec_t *dec);
686
687 static signed char decode_hexdigit[256];
688
689 static UV
690 decode_4hex (dec_t *dec)
691 {
692 signed char d1, d2, d3, d4;
693 unsigned char *cur = (unsigned char *)dec->cur;
694
695 d1 = decode_hexdigit [cur [0]]; if (expect_false (d1 < 0)) ERR ("exactly four hexadecimal digits expected");
696 d2 = decode_hexdigit [cur [1]]; if (expect_false (d2 < 0)) ERR ("exactly four hexadecimal digits expected");
697 d3 = decode_hexdigit [cur [2]]; if (expect_false (d3 < 0)) ERR ("exactly four hexadecimal digits expected");
698 d4 = decode_hexdigit [cur [3]]; if (expect_false (d4 < 0)) ERR ("exactly four hexadecimal digits expected");
699
700 dec->cur += 4;
701
702 return ((UV)d1) << 12
703 | ((UV)d2) << 8
704 | ((UV)d3) << 4
705 | ((UV)d4);
706
707 fail:
708 return (UV)-1;
709 }
710
711 static SV *
712 decode_str (dec_t *dec)
713 {
714 SV *sv = 0;
715 int utf8 = 0;
716 char *dec_cur = dec->cur;
717
718 do
719 {
720 char buf [SHORT_STRING_LEN + UTF8_MAXBYTES];
721 char *cur = buf;
722
723 do
724 {
725 unsigned char ch = *(unsigned char *)dec_cur++;
726
727 if (expect_false (ch == '"'))
728 {
729 --dec_cur;
730 break;
731 }
732 else if (expect_false (ch == '\\'))
733 {
734 switch (*dec_cur)
735 {
736 case '\\':
737 case '/':
738 case '"': *cur++ = *dec_cur++; break;
739
740 case 'b': ++dec_cur; *cur++ = '\010'; break;
741 case 't': ++dec_cur; *cur++ = '\011'; break;
742 case 'n': ++dec_cur; *cur++ = '\012'; break;
743 case 'f': ++dec_cur; *cur++ = '\014'; break;
744 case 'r': ++dec_cur; *cur++ = '\015'; break;
745
746 case 'u':
747 {
748 UV lo, hi;
749 ++dec_cur;
750
751 dec->cur = dec_cur;
752 hi = decode_4hex (dec);
753 dec_cur = dec->cur;
754 if (hi == (UV)-1)
755 goto fail;
756
757 // possibly a surrogate pair
758 if (hi >= 0xd800)
759 if (hi < 0xdc00)
760 {
761 if (dec_cur [0] != '\\' || dec_cur [1] != 'u')
762 ERR ("missing low surrogate character in surrogate pair");
763
764 dec_cur += 2;
765
766 dec->cur = dec_cur;
767 lo = decode_4hex (dec);
768 dec_cur = dec->cur;
769 if (lo == (UV)-1)
770 goto fail;
771
772 if (lo < 0xdc00 || lo >= 0xe000)
773 ERR ("surrogate pair expected");
774
775 hi = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000;
776 }
777 else if (hi < 0xe000)
778 ERR ("missing high surrogate character in surrogate pair");
779
780 if (hi >= 0x80)
781 {
782 utf8 = 1;
783
784 cur = (char *)uvuni_to_utf8_flags (cur, hi, 0);
785 }
786 else
787 *cur++ = hi;
788 }
789 break;
790
791 default:
792 --dec_cur;
793 ERR ("illegal backslash escape sequence in string");
794 }
795 }
796 else if (expect_true (ch >= 0x20 && ch <= 0x7f))
797 *cur++ = ch;
798 else if (ch >= 0x80)
799 {
800 STRLEN clen;
801 UV uch;
802
803 --dec_cur;
804
805 uch = decode_utf8 (dec_cur, dec->end - dec_cur, &clen);
806 if (clen == (STRLEN)-1)
807 ERR ("malformed UTF-8 character in JSON string");
808
809 do
810 *cur++ = *dec_cur++;
811 while (--clen);
812
813 utf8 = 1;
814 }
815 else
816 {
817 --dec_cur;
818
819 if (!ch)
820 ERR ("unexpected end of string while parsing JSON string");
821 else
822 ERR ("invalid character encountered while parsing JSON string");
823 }
824 }
825 while (cur < buf + SHORT_STRING_LEN);
826
827 {
828 STRLEN len = cur - buf;
829
830 if (sv)
831 {
832 SvGROW (sv, SvCUR (sv) + len + 1);
833 memcpy (SvPVX (sv) + SvCUR (sv), buf, len);
834 SvCUR_set (sv, SvCUR (sv) + len);
835 }
836 else
837 sv = newSVpvn (buf, len);
838 }
839 }
840 while (*dec_cur != '"');
841
842 ++dec_cur;
843
844 if (sv)
845 {
846 SvPOK_only (sv);
847 *SvEND (sv) = 0;
848
849 if (utf8)
850 SvUTF8_on (sv);
851 }
852 else
853 sv = newSVpvn ("", 0);
854
855 dec->cur = dec_cur;
856 return sv;
857
858 fail:
859 dec->cur = dec_cur;
860 return 0;
861 }
862
863 static SV *
864 decode_num (dec_t *dec)
865 {
866 int is_nv = 0;
867 char *start = dec->cur;
868
869 // [minus]
870 if (*dec->cur == '-')
871 ++dec->cur;
872
873 if (*dec->cur == '0')
874 {
875 ++dec->cur;
876 if (*dec->cur >= '0' && *dec->cur <= '9')
877 ERR ("malformed number (leading zero must not be followed by another digit)");
878 }
879 else if (*dec->cur < '0' || *dec->cur > '9')
880 ERR ("malformed number (no digits after initial minus)");
881 else
882 do
883 {
884 ++dec->cur;
885 }
886 while (*dec->cur >= '0' && *dec->cur <= '9');
887
888 // [frac]
889 if (*dec->cur == '.')
890 {
891 ++dec->cur;
892
893 if (*dec->cur < '0' || *dec->cur > '9')
894 ERR ("malformed number (no digits after decimal point)");
895
896 do
897 {
898 ++dec->cur;
899 }
900 while (*dec->cur >= '0' && *dec->cur <= '9');
901
902 is_nv = 1;
903 }
904
905 // [exp]
906 if (*dec->cur == 'e' || *dec->cur == 'E')
907 {
908 ++dec->cur;
909
910 if (*dec->cur == '-' || *dec->cur == '+')
911 ++dec->cur;
912
913 if (*dec->cur < '0' || *dec->cur > '9')
914 ERR ("malformed number (no digits after exp sign)");
915
916 do
917 {
918 ++dec->cur;
919 }
920 while (*dec->cur >= '0' && *dec->cur <= '9');
921
922 is_nv = 1;
923 }
924
925 if (!is_nv)
926 {
927 // special case the rather common 1..4-digit-int case, assumes 32 bit ints or so
928 if (*start == '-')
929 switch (dec->cur - start)
930 {
931 case 2: return newSViv (-( start [1] - '0' * 1));
932 case 3: return newSViv (-( start [1] * 10 + start [2] - '0' * 11));
933 case 4: return newSViv (-( start [1] * 100 + start [2] * 10 + start [3] - '0' * 111));
934 case 5: return newSViv (-(start [1] * 1000 + start [2] * 100 + start [3] * 10 + start [4] - '0' * 1111));
935 }
936 else
937 switch (dec->cur - start)
938 {
939 case 1: return newSViv ( start [0] - '0' * 1);
940 case 2: return newSViv ( start [0] * 10 + start [1] - '0' * 11);
941 case 3: return newSViv ( start [0] * 100 + start [1] * 10 + start [2] - '0' * 111);
942 case 4: return newSViv ( start [0] * 1000 + start [1] * 100 + start [2] * 10 + start [3] - '0' * 1111);
943 }
944
945 {
946 UV uv;
947 int numtype = grok_number (start, dec->cur - start, &uv);
948 if (numtype & IS_NUMBER_IN_UV)
949 if (numtype & IS_NUMBER_NEG)
950 {
951 if (uv < (UV)IV_MIN)
952 return newSViv (-(IV)uv);
953 }
954 else
955 return newSVuv (uv);
956
957 // here would likely be the place for bigint support
958 }
959 }
960
961 // if we ever support bigint or bigfloat, this is the place for bigfloat
962 return newSVnv (Atof (start));
963
964 fail:
965 return 0;
966 }
967
968 static SV *
969 decode_av (dec_t *dec)
970 {
971 AV *av = newAV ();
972
973 DEC_INC_DEPTH;
974 decode_ws (dec);
975
976 if (*dec->cur == ']')
977 ++dec->cur;
978 else
979 for (;;)
980 {
981 SV *value;
982
983 value = decode_sv (dec);
984 if (!value)
985 goto fail;
986
987 av_push (av, value);
988
989 decode_ws (dec);
990
991 if (*dec->cur == ']')
992 {
993 ++dec->cur;
994 break;
995 }
996
997 if (*dec->cur != ',')
998 ERR (", or ] expected while parsing array");
999
1000 ++dec->cur;
1001 }
1002
1003 DEC_DEC_DEPTH;
1004 return newRV_noinc ((SV *)av);
1005
1006 fail:
1007 SvREFCNT_dec (av);
1008 DEC_DEC_DEPTH;
1009 return 0;
1010 }
1011
1012 static SV *
1013 decode_hv (dec_t *dec)
1014 {
1015 HV *hv = newHV ();
1016
1017 DEC_INC_DEPTH;
1018 decode_ws (dec);
1019
1020 if (*dec->cur == '}')
1021 ++dec->cur;
1022 else
1023 for (;;)
1024 {
1025 SV *key, *value;
1026
1027 decode_ws (dec); EXPECT_CH ('"');
1028
1029 key = decode_str (dec);
1030 if (!key)
1031 goto fail;
1032
1033 decode_ws (dec); EXPECT_CH (':');
1034
1035 value = decode_sv (dec);
1036 if (!value)
1037 {
1038 SvREFCNT_dec (key);
1039 goto fail;
1040 }
1041
1042 hv_store_ent (hv, key, value, 0);
1043 SvREFCNT_dec (key);
1044
1045 decode_ws (dec);
1046
1047 if (*dec->cur == '}')
1048 {
1049 ++dec->cur;
1050 break;
1051 }
1052
1053 if (*dec->cur != ',')
1054 ERR (", or } expected while parsing object/hash");
1055
1056 ++dec->cur;
1057 }
1058
1059 DEC_DEC_DEPTH;
1060 return newRV_noinc ((SV *)hv);
1061
1062 fail:
1063 SvREFCNT_dec (hv);
1064 DEC_DEC_DEPTH;
1065 return 0;
1066 }
1067
1068 static SV *
1069 decode_sv (dec_t *dec)
1070 {
1071 decode_ws (dec);
1072
1073 // the beauty of JSON: you need exactly one character lookahead
1074 // to parse anything.
1075 switch (*dec->cur)
1076 {
1077 case '"': ++dec->cur; return decode_str (dec);
1078 case '[': ++dec->cur; return decode_av (dec);
1079 case '{': ++dec->cur; return decode_hv (dec);
1080
1081 case '-':
1082 case '0': case '1': case '2': case '3': case '4':
1083 case '5': case '6': case '7': case '8': case '9':
1084 return decode_num (dec);
1085
1086 case 't':
1087 if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "true", 4))
1088 {
1089 dec->cur += 4;
1090 return SvREFCNT_inc (json_true);
1091 }
1092 else
1093 ERR ("'true' expected");
1094
1095 break;
1096
1097 case 'f':
1098 if (dec->end - dec->cur >= 5 && !memcmp (dec->cur, "false", 5))
1099 {
1100 dec->cur += 5;
1101 return SvREFCNT_inc (json_false);
1102 }
1103 else
1104 ERR ("'false' expected");
1105
1106 break;
1107
1108 case 'n':
1109 if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "null", 4))
1110 {
1111 dec->cur += 4;
1112 return newSVsv (&PL_sv_undef);
1113 }
1114 else
1115 ERR ("'null' expected");
1116
1117 break;
1118
1119 default:
1120 ERR ("malformed JSON string, neither array, object, number, string or atom");
1121 break;
1122 }
1123
1124 fail:
1125 return 0;
1126 }
1127
1128 static SV *
1129 decode_json (SV *string, U32 flags, UV *offset_return)
1130 {
1131 dec_t dec;
1132 UV offset;
1133 SV *sv;
1134
1135 SvGETMAGIC (string);
1136 SvUPGRADE (string, SVt_PV);
1137
1138 if (flags & F_UTF8)
1139 sv_utf8_downgrade (string, 0);
1140 else
1141 sv_utf8_upgrade (string);
1142
1143 SvGROW (string, SvCUR (string) + 1); // should basically be a NOP
1144
1145 dec.flags = flags;
1146 dec.cur = SvPVX (string);
1147 dec.end = SvEND (string);
1148 dec.err = 0;
1149 dec.depth = 0;
1150 dec.maxdepth = DEC_DEPTH (dec.flags);
1151
1152 *dec.end = 0; // this should basically be a nop, too, but make sure it's there
1153 sv = decode_sv (&dec);
1154
1155 if (!(offset_return || !sv))
1156 {
1157 // check for trailing garbage
1158 decode_ws (&dec);
1159
1160 if (*dec.cur)
1161 {
1162 dec.err = "garbage after JSON object";
1163 SvREFCNT_dec (sv);
1164 sv = 0;
1165 }
1166 }
1167
1168 if (offset_return || !sv)
1169 {
1170 offset = dec.flags & F_UTF8
1171 ? dec.cur - SvPVX (string)
1172 : utf8_distance (dec.cur, SvPVX (string));
1173
1174 if (offset_return)
1175 *offset_return = offset;
1176 }
1177
1178 if (!sv)
1179 {
1180 SV *uni = sv_newmortal ();
1181
1182 // horrible hack to silence warning inside pv_uni_display
1183 COP cop = *PL_curcop;
1184 cop.cop_warnings = pWARN_NONE;
1185 ENTER;
1186 SAVEVPTR (PL_curcop);
1187 PL_curcop = &cop;
1188 pv_uni_display (uni, dec.cur, dec.end - dec.cur, 20, UNI_DISPLAY_QQ);
1189 LEAVE;
1190
1191 croak ("%s, at character offset %d [\"%s\"]",
1192 dec.err,
1193 (int)offset,
1194 dec.cur != dec.end ? SvPV_nolen (uni) : "(end of string)");
1195 }
1196
1197 sv = sv_2mortal (sv);
1198
1199 if (!(dec.flags & F_ALLOW_NONREF) && !SvROK (sv))
1200 croak ("JSON text must be an object or array (but found number, string, true, false or null, use allow_nonref to allow this)");
1201
1202 return sv;
1203 }
1204
1205 /////////////////////////////////////////////////////////////////////////////
1206 // XS interface functions
1207
1208 MODULE = JSON::XS PACKAGE = JSON::XS
1209
1210 BOOT:
1211 {
1212 int i;
1213
1214 for (i = 0; i < 256; ++i)
1215 decode_hexdigit [i] =
1216 i >= '0' && i <= '9' ? i - '0'
1217 : i >= 'a' && i <= 'f' ? i - 'a' + 10
1218 : i >= 'A' && i <= 'F' ? i - 'A' + 10
1219 : -1;
1220
1221 json_stash = gv_stashpv ("JSON::XS" , 1);
1222 json_boolean_stash = gv_stashpv ("JSON::XS::Boolean", 1);
1223
1224 json_true = get_sv ("JSON::XS::true" , 1); SvREADONLY_on (json_true );
1225 json_false = get_sv ("JSON::XS::false", 1); SvREADONLY_on (json_false);
1226 }
1227
1228 PROTOTYPES: DISABLE
1229
1230 SV *new (char *dummy)
1231 CODE:
1232 RETVAL = sv_bless (newRV_noinc (newSVuv (F_DEFAULT)), json_stash);
1233 OUTPUT:
1234 RETVAL
1235
1236 SV *ascii (SV *self, int enable = 1)
1237 ALIAS:
1238 ascii = F_ASCII
1239 latin1 = F_LATIN1
1240 utf8 = F_UTF8
1241 indent = F_INDENT
1242 canonical = F_CANONICAL
1243 space_before = F_SPACE_BEFORE
1244 space_after = F_SPACE_AFTER
1245 pretty = F_PRETTY
1246 allow_nonref = F_ALLOW_NONREF
1247 shrink = F_SHRINK
1248 allow_blessed = F_ALLOW_BLESSED
1249 convert_blessed = F_CONV_BLESSED
1250 CODE:
1251 {
1252 UV *uv = SvJSON (self);
1253 if (enable)
1254 *uv |= ix;
1255 else
1256 *uv &= ~ix;
1257
1258 RETVAL = newSVsv (self);
1259 }
1260 OUTPUT:
1261 RETVAL
1262
1263 SV *max_depth (SV *self, UV max_depth = 0x80000000UL)
1264 CODE:
1265 {
1266 UV *uv = SvJSON (self);
1267 UV log2 = 0;
1268
1269 if (max_depth > 0x80000000UL) max_depth = 0x80000000UL;
1270
1271 while ((1UL << log2) < max_depth)
1272 ++log2;
1273
1274 *uv = *uv & ~F_MAXDEPTH | (log2 << S_MAXDEPTH);
1275
1276 RETVAL = newSVsv (self);
1277 }
1278 OUTPUT:
1279 RETVAL
1280
1281 void encode (SV *self, SV *scalar)
1282 PPCODE:
1283 XPUSHs (encode_json (scalar, *SvJSON (self)));
1284
1285 void decode (SV *self, SV *jsonstr)
1286 PPCODE:
1287 XPUSHs (decode_json (jsonstr, *SvJSON (self), 0));
1288
1289 void decode_prefix (SV *self, SV *jsonstr)
1290 PPCODE:
1291 {
1292 UV offset;
1293 EXTEND (SP, 2);
1294 PUSHs (decode_json (jsonstr, *SvJSON (self), &offset));
1295 PUSHs (sv_2mortal (newSVuv (offset)));
1296 }
1297
1298 PROTOTYPES: ENABLE
1299
1300 void to_json (SV *scalar)
1301 ALIAS:
1302 objToJson = 0
1303 PPCODE:
1304 XPUSHs (encode_json (scalar, F_DEFAULT | F_UTF8));
1305
1306 void from_json (SV *jsonstr)
1307 ALIAS:
1308 jsonToObj = 0
1309 PPCODE:
1310 XPUSHs (decode_json (jsonstr, F_DEFAULT | F_UTF8, 0));
1311