ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/JSON-XS/XS.xs
Revision: 1.49
Committed: Sun Jul 1 23:40:07 2007 UTC (16 years, 10 months ago) by root
Branch: MAIN
Changes since 1.48: +67 -8 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
31 #define F_MAXDEPTH 0xf8000000UL
32 #define S_MAXDEPTH 27
33 #define F_MAXSIZE 0x01f00000UL
34 #define S_MAXSIZE 20
35 #define F_HOOK 0x00080000UL // some hooks exist, so slow-path processing
36
37 #define DEC_DEPTH(flags) (1UL << ((flags & F_MAXDEPTH) >> S_MAXDEPTH))
38 #define DEC_SIZE(flags) (1UL << ((flags & F_MAXSIZE ) >> S_MAXSIZE ))
39
40 #define F_PRETTY F_INDENT | F_SPACE_BEFORE | F_SPACE_AFTER
41 #define F_DEFAULT (9UL << S_MAXDEPTH)
42
43 #define INIT_SIZE 32 // initial scalar size to be allocated
44 #define INDENT_STEP 3 // spaces per indentation level
45
46 #define SHORT_STRING_LEN 16384 // special-case strings of up to this size
47
48 #define SB do {
49 #define SE } while (0)
50
51 #if __GNUC__ >= 3
52 # define expect(expr,value) __builtin_expect ((expr),(value))
53 # define inline inline
54 #else
55 # define expect(expr,value) (expr)
56 # define inline static
57 #endif
58
59 #define expect_false(expr) expect ((expr) != 0, 0)
60 #define expect_true(expr) expect ((expr) != 0, 1)
61
62 static HV *json_stash, *json_boolean_stash; // JSON::XS::
63 static SV *json_true, *json_false;
64
65 typedef struct {
66 U32 flags;
67 SV *cb_object, *cb_sk_object;
68 } JSON;
69
70 /////////////////////////////////////////////////////////////////////////////
71 // utility functions
72
73 inline 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 JSON json;
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->json.flags & F_ASCII || (enc->json.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->json.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->json.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->json.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->json.flags & F_INDENT)
290 encode_nl (enc);
291 else if (enc->json.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->json.flags & F_SPACE_BEFORE) encode_space (enc);
345 encode_ch (enc, ':');
346 if (enc->json.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->json.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->json.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; ENTER; SAVETMPS; PUSHMARK (SP);
498 XPUSHs (sv_bless (sv_2mortal (newRV_inc (sv)), SvSTASH (sv)));
499
500 // calling with G_SCALAR ensures that we always get a 1 reutrn value
501 // check anyways.
502 PUTBACK;
503 assert (1 == call_sv ((SV *)GvCV (to_json), G_SCALAR));
504 SPAGAIN;
505
506 encode_sv (enc, POPs);
507
508 FREETMPS; LEAVE;
509 }
510 else if (enc->json.flags & F_ALLOW_BLESSED)
511 encode_str (enc, "null", 4, 0);
512 else
513 croak ("encountered object '%s', but neither allow_blessed enabled nor TO_JSON method available on it",
514 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
515 }
516 else if (enc->json.flags & F_ALLOW_BLESSED)
517 encode_str (enc, "null", 4, 0);
518 else
519 croak ("encountered object '%s', but neither allow_blessed nor convert_blessed settings are enabled",
520 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
521 }
522 }
523 else if (svt == SVt_PVHV)
524 encode_hv (enc, (HV *)sv);
525 else if (svt == SVt_PVAV)
526 encode_av (enc, (AV *)sv);
527 else if (svt < SVt_PVAV)
528 {
529 if (SvNIOK (sv) && SvIV (sv) == 0)
530 encode_str (enc, "false", 5, 0);
531 else if (SvNIOK (sv) && SvIV (sv) == 1)
532 encode_str (enc, "true", 4, 0);
533 else
534 croak ("cannot encode reference to scalar '%s' unless the scalar is 0 or 1",
535 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
536 }
537 else
538 croak ("encountered %s, but JSON can only represent references to arrays or hashes",
539 SvPV_nolen (sv_2mortal (newRV_inc (sv))));
540 }
541
542 static void
543 encode_sv (enc_t *enc, SV *sv)
544 {
545 SvGETMAGIC (sv);
546
547 if (SvPOKp (sv))
548 {
549 STRLEN len;
550 char *str = SvPV (sv, len);
551 encode_ch (enc, '"');
552 encode_str (enc, str, len, SvUTF8 (sv));
553 encode_ch (enc, '"');
554 }
555 else if (SvNOKp (sv))
556 {
557 // trust that perl will do the right thing w.r.t. JSON syntax.
558 need (enc, NV_DIG + 32);
559 Gconvert (SvNVX (sv), NV_DIG, 0, enc->cur);
560 enc->cur += strlen (enc->cur);
561 }
562 else if (SvIOKp (sv))
563 {
564 // we assume we can always read an IV as a UV
565 if (SvUV (sv) & ~(UV)0x7fff)
566 {
567 // large integer, use the (rather slow) snprintf way.
568 need (enc, sizeof (UV) * 3);
569 enc->cur +=
570 SvIsUV(sv)
571 ? snprintf (enc->cur, sizeof (UV) * 3, "%"UVuf, (UV)SvUVX (sv))
572 : snprintf (enc->cur, sizeof (UV) * 3, "%"IVdf, (IV)SvIVX (sv));
573 }
574 else
575 {
576 // optimise the "small number case"
577 // code will likely be branchless and use only a single multiplication
578 I32 i = SvIV (sv);
579 U32 u;
580 char digit, nz = 0;
581
582 need (enc, 6);
583
584 *enc->cur = '-'; enc->cur += i < 0 ? 1 : 0;
585 u = i < 0 ? -i : i;
586
587 // convert to 4.28 fixed-point representation
588 u = u * ((0xfffffff + 10000) / 10000); // 10**5, 5 fractional digits
589
590 // now output digit by digit, each time masking out the integer part
591 // and multiplying by 5 while moving the decimal point one to the right,
592 // resulting in a net multiplication by 10.
593 // we always write the digit to memory but conditionally increment
594 // the pointer, to ease the usage of conditional move instructions.
595 digit = u >> 28; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0xfffffff) * 5;
596 digit = u >> 27; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x7ffffff) * 5;
597 digit = u >> 26; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x3ffffff) * 5;
598 digit = u >> 25; *enc->cur = digit + '0'; enc->cur += (nz = nz || digit); u = (u & 0x1ffffff) * 5;
599 digit = u >> 24; *enc->cur = digit + '0'; enc->cur += 1; // correctly generate '0'
600 }
601 }
602 else if (SvROK (sv))
603 encode_rv (enc, SvRV (sv));
604 else if (!SvOK (sv))
605 encode_str (enc, "null", 4, 0);
606 else
607 croak ("encountered perl type (%s,0x%x) that JSON cannot handle, you might want to report this",
608 SvPV_nolen (sv), SvFLAGS (sv));
609 }
610
611 static SV *
612 encode_json (SV *scalar, JSON *json)
613 {
614 enc_t enc;
615
616 if (!(json->flags & F_ALLOW_NONREF) && !SvROK (scalar))
617 croak ("hash- or arrayref expected (not a simple scalar, use allow_nonref to allow this)");
618
619 enc.json = *json;
620 enc.sv = sv_2mortal (NEWSV (0, INIT_SIZE));
621 enc.cur = SvPVX (enc.sv);
622 enc.end = SvEND (enc.sv);
623 enc.indent = 0;
624 enc.maxdepth = DEC_DEPTH (enc.json.flags);
625
626 SvPOK_only (enc.sv);
627 encode_sv (&enc, scalar);
628
629 SvCUR_set (enc.sv, enc.cur - SvPVX (enc.sv));
630 *SvEND (enc.sv) = 0; // many xs functions expect a trailing 0 for text strings
631
632 if (!(enc.json.flags & (F_ASCII | F_LATIN1 | F_UTF8)))
633 SvUTF8_on (enc.sv);
634
635 if (enc.json.flags & F_SHRINK)
636 shrink (enc.sv);
637
638 return enc.sv;
639 }
640
641 /////////////////////////////////////////////////////////////////////////////
642 // decoder
643
644 // structure used for decoding JSON
645 typedef struct
646 {
647 char *cur; // current parser pointer
648 char *end; // end of input string
649 const char *err; // parse error, if != 0
650 JSON json;
651 U32 depth; // recursion depth
652 U32 maxdepth; // recursion depth limit
653 } dec_t;
654
655 inline void
656 decode_ws (dec_t *dec)
657 {
658 for (;;)
659 {
660 char ch = *dec->cur;
661
662 if (ch > 0x20
663 || (ch != 0x20 && ch != 0x0a && ch != 0x0d && ch != 0x09))
664 break;
665
666 ++dec->cur;
667 }
668 }
669
670 #define ERR(reason) SB dec->err = reason; goto fail; SE
671
672 #define EXPECT_CH(ch) SB \
673 if (*dec->cur != ch) \
674 ERR (# ch " expected"); \
675 ++dec->cur; \
676 SE
677
678 #define DEC_INC_DEPTH if (++dec->depth > dec->maxdepth) ERR ("json datastructure exceeds maximum nesting level (set a higher max_depth)")
679 #define DEC_DEC_DEPTH --dec->depth
680
681 static SV *decode_sv (dec_t *dec);
682
683 static signed char decode_hexdigit[256];
684
685 static UV
686 decode_4hex (dec_t *dec)
687 {
688 signed char d1, d2, d3, d4;
689 unsigned char *cur = (unsigned char *)dec->cur;
690
691 d1 = decode_hexdigit [cur [0]]; if (expect_false (d1 < 0)) ERR ("exactly four hexadecimal digits expected");
692 d2 = decode_hexdigit [cur [1]]; if (expect_false (d2 < 0)) ERR ("exactly four hexadecimal digits expected");
693 d3 = decode_hexdigit [cur [2]]; if (expect_false (d3 < 0)) ERR ("exactly four hexadecimal digits expected");
694 d4 = decode_hexdigit [cur [3]]; if (expect_false (d4 < 0)) ERR ("exactly four hexadecimal digits expected");
695
696 dec->cur += 4;
697
698 return ((UV)d1) << 12
699 | ((UV)d2) << 8
700 | ((UV)d3) << 4
701 | ((UV)d4);
702
703 fail:
704 return (UV)-1;
705 }
706
707 static SV *
708 decode_str (dec_t *dec)
709 {
710 SV *sv = 0;
711 int utf8 = 0;
712 char *dec_cur = dec->cur;
713
714 do
715 {
716 char buf [SHORT_STRING_LEN + UTF8_MAXBYTES];
717 char *cur = buf;
718
719 do
720 {
721 unsigned char ch = *(unsigned char *)dec_cur++;
722
723 if (expect_false (ch == '"'))
724 {
725 --dec_cur;
726 break;
727 }
728 else if (expect_false (ch == '\\'))
729 {
730 switch (*dec_cur)
731 {
732 case '\\':
733 case '/':
734 case '"': *cur++ = *dec_cur++; break;
735
736 case 'b': ++dec_cur; *cur++ = '\010'; break;
737 case 't': ++dec_cur; *cur++ = '\011'; break;
738 case 'n': ++dec_cur; *cur++ = '\012'; break;
739 case 'f': ++dec_cur; *cur++ = '\014'; break;
740 case 'r': ++dec_cur; *cur++ = '\015'; break;
741
742 case 'u':
743 {
744 UV lo, hi;
745 ++dec_cur;
746
747 dec->cur = dec_cur;
748 hi = decode_4hex (dec);
749 dec_cur = dec->cur;
750 if (hi == (UV)-1)
751 goto fail;
752
753 // possibly a surrogate pair
754 if (hi >= 0xd800)
755 if (hi < 0xdc00)
756 {
757 if (dec_cur [0] != '\\' || dec_cur [1] != 'u')
758 ERR ("missing low surrogate character in surrogate pair");
759
760 dec_cur += 2;
761
762 dec->cur = dec_cur;
763 lo = decode_4hex (dec);
764 dec_cur = dec->cur;
765 if (lo == (UV)-1)
766 goto fail;
767
768 if (lo < 0xdc00 || lo >= 0xe000)
769 ERR ("surrogate pair expected");
770
771 hi = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000;
772 }
773 else if (hi < 0xe000)
774 ERR ("missing high surrogate character in surrogate pair");
775
776 if (hi >= 0x80)
777 {
778 utf8 = 1;
779
780 cur = (char *)uvuni_to_utf8_flags (cur, hi, 0);
781 }
782 else
783 *cur++ = hi;
784 }
785 break;
786
787 default:
788 --dec_cur;
789 ERR ("illegal backslash escape sequence in string");
790 }
791 }
792 else if (expect_true (ch >= 0x20 && ch <= 0x7f))
793 *cur++ = ch;
794 else if (ch >= 0x80)
795 {
796 STRLEN clen;
797 UV uch;
798
799 --dec_cur;
800
801 uch = decode_utf8 (dec_cur, dec->end - dec_cur, &clen);
802 if (clen == (STRLEN)-1)
803 ERR ("malformed UTF-8 character in JSON string");
804
805 do
806 *cur++ = *dec_cur++;
807 while (--clen);
808
809 utf8 = 1;
810 }
811 else
812 {
813 --dec_cur;
814
815 if (!ch)
816 ERR ("unexpected end of string while parsing JSON string");
817 else
818 ERR ("invalid character encountered while parsing JSON string");
819 }
820 }
821 while (cur < buf + SHORT_STRING_LEN);
822
823 {
824 STRLEN len = cur - buf;
825
826 if (sv)
827 {
828 SvGROW (sv, SvCUR (sv) + len + 1);
829 memcpy (SvPVX (sv) + SvCUR (sv), buf, len);
830 SvCUR_set (sv, SvCUR (sv) + len);
831 }
832 else
833 sv = newSVpvn (buf, len);
834 }
835 }
836 while (*dec_cur != '"');
837
838 ++dec_cur;
839
840 if (sv)
841 {
842 SvPOK_only (sv);
843 *SvEND (sv) = 0;
844
845 if (utf8)
846 SvUTF8_on (sv);
847 }
848 else
849 sv = newSVpvn ("", 0);
850
851 dec->cur = dec_cur;
852 return sv;
853
854 fail:
855 dec->cur = dec_cur;
856 return 0;
857 }
858
859 static SV *
860 decode_num (dec_t *dec)
861 {
862 int is_nv = 0;
863 char *start = dec->cur;
864
865 // [minus]
866 if (*dec->cur == '-')
867 ++dec->cur;
868
869 if (*dec->cur == '0')
870 {
871 ++dec->cur;
872 if (*dec->cur >= '0' && *dec->cur <= '9')
873 ERR ("malformed number (leading zero must not be followed by another digit)");
874 }
875 else if (*dec->cur < '0' || *dec->cur > '9')
876 ERR ("malformed number (no digits after initial minus)");
877 else
878 do
879 {
880 ++dec->cur;
881 }
882 while (*dec->cur >= '0' && *dec->cur <= '9');
883
884 // [frac]
885 if (*dec->cur == '.')
886 {
887 ++dec->cur;
888
889 if (*dec->cur < '0' || *dec->cur > '9')
890 ERR ("malformed number (no digits after decimal point)");
891
892 do
893 {
894 ++dec->cur;
895 }
896 while (*dec->cur >= '0' && *dec->cur <= '9');
897
898 is_nv = 1;
899 }
900
901 // [exp]
902 if (*dec->cur == 'e' || *dec->cur == 'E')
903 {
904 ++dec->cur;
905
906 if (*dec->cur == '-' || *dec->cur == '+')
907 ++dec->cur;
908
909 if (*dec->cur < '0' || *dec->cur > '9')
910 ERR ("malformed number (no digits after exp sign)");
911
912 do
913 {
914 ++dec->cur;
915 }
916 while (*dec->cur >= '0' && *dec->cur <= '9');
917
918 is_nv = 1;
919 }
920
921 if (!is_nv)
922 {
923 // special case the rather common 1..4-digit-int case, assumes 32 bit ints or so
924 if (*start == '-')
925 switch (dec->cur - start)
926 {
927 case 2: return newSViv (-( start [1] - '0' * 1));
928 case 3: return newSViv (-( start [1] * 10 + start [2] - '0' * 11));
929 case 4: return newSViv (-( start [1] * 100 + start [2] * 10 + start [3] - '0' * 111));
930 case 5: return newSViv (-(start [1] * 1000 + start [2] * 100 + start [3] * 10 + start [4] - '0' * 1111));
931 }
932 else
933 switch (dec->cur - start)
934 {
935 case 1: return newSViv ( start [0] - '0' * 1);
936 case 2: return newSViv ( start [0] * 10 + start [1] - '0' * 11);
937 case 3: return newSViv ( start [0] * 100 + start [1] * 10 + start [2] - '0' * 111);
938 case 4: return newSViv ( start [0] * 1000 + start [1] * 100 + start [2] * 10 + start [3] - '0' * 1111);
939 }
940
941 {
942 UV uv;
943 int numtype = grok_number (start, dec->cur - start, &uv);
944 if (numtype & IS_NUMBER_IN_UV)
945 if (numtype & IS_NUMBER_NEG)
946 {
947 if (uv < (UV)IV_MIN)
948 return newSViv (-(IV)uv);
949 }
950 else
951 return newSVuv (uv);
952
953 // here would likely be the place for bigint support
954 }
955 }
956
957 // if we ever support bigint or bigfloat, this is the place for bigfloat
958 return newSVnv (Atof (start));
959
960 fail:
961 return 0;
962 }
963
964 static SV *
965 decode_av (dec_t *dec)
966 {
967 AV *av = newAV ();
968
969 DEC_INC_DEPTH;
970 decode_ws (dec);
971
972 if (*dec->cur == ']')
973 ++dec->cur;
974 else
975 for (;;)
976 {
977 SV *value;
978
979 value = decode_sv (dec);
980 if (!value)
981 goto fail;
982
983 av_push (av, value);
984
985 decode_ws (dec);
986
987 if (*dec->cur == ']')
988 {
989 ++dec->cur;
990 break;
991 }
992
993 if (*dec->cur != ',')
994 ERR (", or ] expected while parsing array");
995
996 ++dec->cur;
997 }
998
999 DEC_DEC_DEPTH;
1000 return newRV_noinc ((SV *)av);
1001
1002 fail:
1003 SvREFCNT_dec (av);
1004 DEC_DEC_DEPTH;
1005 return 0;
1006 }
1007
1008 static SV *
1009 decode_hv (dec_t *dec)
1010 {
1011 SV *sv;
1012 HV *hv = newHV ();
1013
1014 DEC_INC_DEPTH;
1015 decode_ws (dec);
1016
1017 if (*dec->cur == '}')
1018 ++dec->cur;
1019 else
1020 for (;;)
1021 {
1022 decode_ws (dec); EXPECT_CH ('"');
1023
1024 // heuristic: assume that
1025 // a) decode_str + hv_store_ent are abysmally slow.
1026 // b) most hash keys are short, simple ascii text.
1027 // => try to "fast-match" such strings to avoid
1028 // the overhead of decode_str + hv_store_ent.
1029 {
1030 SV *value;
1031 char *p = dec->cur;
1032 char *e = p + 24; // only try up to 24 bytes
1033
1034 for (;;)
1035 {
1036 // the >= 0x80 is true on most architectures
1037 if (p == e || *p < 0x20 || *p >= 0x80 || *p == '\\')
1038 {
1039 // slow path, back up and use decode_str
1040 SV *key = decode_str (dec);
1041 if (!key)
1042 goto fail;
1043
1044 decode_ws (dec); EXPECT_CH (':');
1045
1046 value = decode_sv (dec);
1047 if (!value)
1048 {
1049 SvREFCNT_dec (key);
1050 goto fail;
1051 }
1052
1053 hv_store_ent (hv, key, value, 0);
1054 SvREFCNT_dec (key);
1055
1056 break;
1057 }
1058 else if (*p == '"')
1059 {
1060 // fast path, got a simple key
1061 char *key = dec->cur;
1062 int len = p - key;
1063 dec->cur = p + 1;
1064
1065 decode_ws (dec); EXPECT_CH (':');
1066
1067 value = decode_sv (dec);
1068 if (!value)
1069 goto fail;
1070
1071 hv_store (hv, key, len, value, 0);
1072
1073 break;
1074 }
1075
1076 ++p;
1077 }
1078 }
1079
1080 decode_ws (dec);
1081
1082 if (*dec->cur == '}')
1083 {
1084 ++dec->cur;
1085 break;
1086 }
1087
1088 if (*dec->cur != ',')
1089 ERR (", or } expected while parsing object/hash");
1090
1091 ++dec->cur;
1092 }
1093
1094 DEC_DEC_DEPTH;
1095 sv = newRV_noinc ((SV *)hv);
1096
1097 // check filter callbacks
1098 if (dec->json.flags & F_HOOK)
1099 {
1100 ENTER; SAVETMPS;
1101
1102 if (HvKEYS (hv) == 1 && dec->json.cb_sk_object)
1103 {
1104 int count;
1105
1106 dSP; PUSHMARK (SP);
1107 XPUSHs (sv_2mortal (sv));
1108
1109 PUTBACK; count = call_sv (dec->json.cb_sk_object, G_ARRAY); SPAGAIN;
1110
1111 if (count == 1)
1112 sv = newSVsv (POPs);
1113 else
1114 SvREFCNT_inc (sv);
1115 }
1116
1117 if (dec->json.cb_object)
1118 {
1119 int count;
1120
1121 dSP; ENTER; SAVETMPS; PUSHMARK (SP);
1122 XPUSHs (sv_2mortal (sv));
1123
1124 PUTBACK; count = call_sv (dec->json.cb_object, G_ARRAY); SPAGAIN;
1125
1126 if (count == 1)
1127 sv = newSVsv (POPs);
1128 else
1129 SvREFCNT_inc (sv);
1130 }
1131
1132 FREETMPS; LEAVE;
1133 }
1134
1135 return newRV_noinc ((SV *)hv);
1136
1137 fail:
1138 SvREFCNT_dec (hv);
1139 DEC_DEC_DEPTH;
1140 return 0;
1141 }
1142
1143 static SV *
1144 decode_sv (dec_t *dec)
1145 {
1146 decode_ws (dec);
1147
1148 // the beauty of JSON: you need exactly one character lookahead
1149 // to parse anything.
1150 switch (*dec->cur)
1151 {
1152 case '"': ++dec->cur; return decode_str (dec);
1153 case '[': ++dec->cur; return decode_av (dec);
1154 case '{': ++dec->cur; return decode_hv (dec);
1155
1156 case '-':
1157 case '0': case '1': case '2': case '3': case '4':
1158 case '5': case '6': case '7': case '8': case '9':
1159 return decode_num (dec);
1160
1161 case 't':
1162 if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "true", 4))
1163 {
1164 dec->cur += 4;
1165 return SvREFCNT_inc (json_true);
1166 }
1167 else
1168 ERR ("'true' expected");
1169
1170 break;
1171
1172 case 'f':
1173 if (dec->end - dec->cur >= 5 && !memcmp (dec->cur, "false", 5))
1174 {
1175 dec->cur += 5;
1176 return SvREFCNT_inc (json_false);
1177 }
1178 else
1179 ERR ("'false' expected");
1180
1181 break;
1182
1183 case 'n':
1184 if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "null", 4))
1185 {
1186 dec->cur += 4;
1187 return newSVsv (&PL_sv_undef);
1188 }
1189 else
1190 ERR ("'null' expected");
1191
1192 break;
1193
1194 default:
1195 ERR ("malformed JSON string, neither array, object, number, string or atom");
1196 break;
1197 }
1198
1199 fail:
1200 return 0;
1201 }
1202
1203 static SV *
1204 decode_json (SV *string, JSON *json, UV *offset_return)
1205 {
1206 dec_t dec;
1207 UV offset;
1208 SV *sv;
1209
1210 SvGETMAGIC (string);
1211 SvUPGRADE (string, SVt_PV);
1212
1213 if (json->flags & F_MAXSIZE && SvCUR (string) > DEC_SIZE (json->flags))
1214 croak ("attempted decode of JSON text of %lu bytes size, but max_size is set to %lu",
1215 (unsigned long)SvCUR (string), (unsigned long)DEC_SIZE (json->flags));
1216
1217 if (json->flags & F_UTF8)
1218 sv_utf8_downgrade (string, 0);
1219 else
1220 sv_utf8_upgrade (string);
1221
1222 SvGROW (string, SvCUR (string) + 1); // should basically be a NOP
1223
1224 dec.json = *json;
1225 dec.cur = SvPVX (string);
1226 dec.end = SvEND (string);
1227 dec.err = 0;
1228 dec.depth = 0;
1229 dec.maxdepth = DEC_DEPTH (dec.json.flags);
1230
1231 if (dec.json.cb_object || dec.json.cb_sk_object)
1232 dec.json.flags |= F_HOOK;
1233
1234 *dec.end = 0; // this should basically be a nop, too, but make sure it's there
1235 sv = decode_sv (&dec);
1236
1237 if (!(offset_return || !sv))
1238 {
1239 // check for trailing garbage
1240 decode_ws (&dec);
1241
1242 if (*dec.cur)
1243 {
1244 dec.err = "garbage after JSON object";
1245 SvREFCNT_dec (sv);
1246 sv = 0;
1247 }
1248 }
1249
1250 if (offset_return || !sv)
1251 {
1252 offset = dec.json.flags & F_UTF8
1253 ? dec.cur - SvPVX (string)
1254 : utf8_distance (dec.cur, SvPVX (string));
1255
1256 if (offset_return)
1257 *offset_return = offset;
1258 }
1259
1260 if (!sv)
1261 {
1262 SV *uni = sv_newmortal ();
1263
1264 // horrible hack to silence warning inside pv_uni_display
1265 COP cop = *PL_curcop;
1266 cop.cop_warnings = pWARN_NONE;
1267 ENTER;
1268 SAVEVPTR (PL_curcop);
1269 PL_curcop = &cop;
1270 pv_uni_display (uni, dec.cur, dec.end - dec.cur, 20, UNI_DISPLAY_QQ);
1271 LEAVE;
1272
1273 croak ("%s, at character offset %d [\"%s\"]",
1274 dec.err,
1275 (int)offset,
1276 dec.cur != dec.end ? SvPV_nolen (uni) : "(end of string)");
1277 }
1278
1279 sv = sv_2mortal (sv);
1280
1281 if (!(dec.json.flags & F_ALLOW_NONREF) && !SvROK (sv))
1282 croak ("JSON text must be an object or array (but found number, string, true, false or null, use allow_nonref to allow this)");
1283
1284 return sv;
1285 }
1286
1287 /////////////////////////////////////////////////////////////////////////////
1288 // XS interface functions
1289
1290 MODULE = JSON::XS PACKAGE = JSON::XS
1291
1292 BOOT:
1293 {
1294 int i;
1295
1296 for (i = 0; i < 256; ++i)
1297 decode_hexdigit [i] =
1298 i >= '0' && i <= '9' ? i - '0'
1299 : i >= 'a' && i <= 'f' ? i - 'a' + 10
1300 : i >= 'A' && i <= 'F' ? i - 'A' + 10
1301 : -1;
1302
1303 json_stash = gv_stashpv ("JSON::XS" , 1);
1304 json_boolean_stash = gv_stashpv ("JSON::XS::Boolean", 1);
1305
1306 json_true = get_sv ("JSON::XS::true" , 1); SvREADONLY_on (json_true );
1307 json_false = get_sv ("JSON::XS::false", 1); SvREADONLY_on (json_false);
1308 }
1309
1310 PROTOTYPES: DISABLE
1311
1312 void new (char *klass)
1313 PPCODE:
1314 {
1315 SV *pv = NEWSV (0, sizeof (JSON));
1316 SvPOK_only (pv);
1317 Zero (SvPVX (pv), 1, JSON);
1318 ((JSON *)SvPVX (pv))->flags = F_DEFAULT;
1319 XPUSHs (sv_2mortal (sv_bless (newRV_noinc (pv), json_stash)));
1320 }
1321
1322 void ascii (JSON *self, int enable = 1)
1323 ALIAS:
1324 ascii = F_ASCII
1325 latin1 = F_LATIN1
1326 utf8 = F_UTF8
1327 indent = F_INDENT
1328 canonical = F_CANONICAL
1329 space_before = F_SPACE_BEFORE
1330 space_after = F_SPACE_AFTER
1331 pretty = F_PRETTY
1332 allow_nonref = F_ALLOW_NONREF
1333 shrink = F_SHRINK
1334 allow_blessed = F_ALLOW_BLESSED
1335 convert_blessed = F_CONV_BLESSED
1336 PPCODE:
1337 {
1338 if (enable)
1339 self->flags |= ix;
1340 else
1341 self->flags &= ~ix;
1342
1343 XPUSHs (ST (0));
1344 }
1345
1346 void max_depth (JSON *self, UV max_depth = 0x80000000UL)
1347 PPCODE:
1348 {
1349 UV log2 = 0;
1350
1351 if (max_depth > 0x80000000UL) max_depth = 0x80000000UL;
1352
1353 while ((1UL << log2) < max_depth)
1354 ++log2;
1355
1356 self->flags = self->flags & ~F_MAXDEPTH | (log2 << S_MAXDEPTH);
1357
1358 XPUSHs (ST (0));
1359 }
1360
1361 void max_size (JSON *self, UV max_size = 0)
1362 PPCODE:
1363 {
1364 UV log2 = 0;
1365
1366 if (max_size > 0x80000000UL) max_size = 0x80000000UL;
1367 if (max_size == 1) max_size = 2;
1368
1369 while ((1UL << log2) < max_size)
1370 ++log2;
1371
1372 self->flags = self->flags & ~F_MAXSIZE | (log2 << S_MAXSIZE);
1373
1374 XPUSHs (ST (0));
1375 }
1376
1377 void filter_json_objects (JSON *self, SV *cb = &PL_sv_undef)
1378 ALIAS:
1379 filter_sk_json_objects = 1
1380 PPCODE:
1381 {
1382 if (!SvOK (cb))
1383 cb = 0;
1384
1385 switch (ix)
1386 {
1387 case 0: self->cb_object = cb; break;
1388 case 1: self->cb_sk_object = cb; break;
1389 }
1390
1391 XPUSHs (ST (0));
1392 }
1393
1394 void encode (JSON *self, SV *scalar)
1395 PPCODE:
1396 XPUSHs (encode_json (scalar, self));
1397
1398 void decode (JSON *self, SV *jsonstr)
1399 PPCODE:
1400 XPUSHs (decode_json (jsonstr, self, 0));
1401
1402 void decode_prefix (JSON *self, SV *jsonstr)
1403 PPCODE:
1404 {
1405 UV offset;
1406 EXTEND (SP, 2);
1407 PUSHs (decode_json (jsonstr, self, &offset));
1408 PUSHs (sv_2mortal (newSVuv (offset)));
1409 }
1410
1411 PROTOTYPES: ENABLE
1412
1413 void to_json (SV *scalar)
1414 PPCODE:
1415 {
1416 JSON json = { F_DEFAULT | F_UTF8 };
1417 XPUSHs (encode_json (scalar, &json));
1418 }
1419
1420 void from_json (SV *jsonstr)
1421 PPCODE:
1422 {
1423 JSON json = { F_DEFAULT | F_UTF8 };
1424 XPUSHs (decode_json (jsonstr, &json, 0));
1425 }
1426