JSON-XS/XS.xs

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include "assert.h"
#include "string.h"
#include "stdlib.h"

#define F_ASCII        0x00000001
#define F_UTF8         0x00000002
#define F_INDENT       0x00000004
#define F_CANONICAL    0x00000008
#define F_SPACE_BEFORE 0x00000010
#define F_SPACE_AFTER  0x00000020
#define F_JSON_RPC     0x00000040

#define F_PRETTY    F_INDENT | F_SPACE_BEFORE | F_SPACE_AFTER
#define F_DEFAULT   0

#define INIT_SIZE   32 // initial scalar size to be allocated

#define SB do {
#define SE } while (0)

static HV *json_stash;

// structure used for encoding JSON
typedef struct
{
  char *cur;
  STRLEN len; // SvLEN (sv)
  char *end;  // SvEND (sv)
  SV *sv;
  UV flags;
  int max_recurse;
  int indent;
} enc_t;

// structure used for decoding JSON
typedef struct
{
  char *cur;
  char *end;
  char *err;
  UV flags;
} dec_t;

static UV *
SvJSON (SV *sv)
{
  if (!(SvROK (sv) && SvOBJECT (SvRV (sv)) && SvSTASH (SvRV (sv)) == json_stash))
    croak ("object is not of type JSON::XS");

  return &SvUVX (SvRV (sv));
}

/////////////////////////////////////////////////////////////////////////////

static void
need (enc_t *enc, STRLEN len)
{
  if (enc->cur + len >= enc->end)
    {
      STRLEN cur = enc->cur - SvPVX (enc->sv);
      SvGROW (enc->sv, cur + len + 1);
      enc->cur = SvPVX (enc->sv) + cur;
      enc->end = SvEND (enc->sv);
    }
}

static void
encode_ch (enc_t *enc, char ch)
{
  need (enc, 1);
  *enc->cur++ = ch;
}

static void
encode_str (enc_t *enc, char *str, STRLEN len, int is_utf8)
{
  char *end = str + len;

  while (str < end)
    {
      unsigned char ch = *(unsigned char *)str;
      if (ch >= 0x20 && ch < 0x80) // most common case
        {
          *enc->cur++ = ch;
          str++;
        }
      else
        {
          STRLEN clen;
          UV uch;

          if (is_utf8)
            {
              uch = utf8n_to_uvuni (str, end - str, &clen, UTF8_CHECK_ONLY);
              if (clen < 0)
                croak ("malformed UTF-8 character in string, cannot convert to JSON");
            }
          else
            {
              uch = ch;
              clen = 1;
            }

          need (enc, len += 6);

          if (uch < 0xa0 || enc->flags & F_ASCII)
            {
              if (uch > 0xFFFFUL)
                {
                  len += 6;
                  need (enc, len += 6);
                  sprintf (enc->cur, "\\u%04x\\u%04x",
                           (uch - 0x10000) / 0x400 + 0xD800,
                           (uch - 0x10000) % 0x400 + 0xDC00);
                  enc->cur += 12;
                }
              else
                {
                  sprintf (enc->cur, "\\u%04x", uch);
                  enc->cur += 6;
                }
            }
          else if (is_utf8)
            {
              memcpy (enc->cur, str, clen);
              enc->cur += clen;
            }
          else
            enc->cur = uvuni_to_utf8_flags (enc->cur, uch, 0);

          str += clen;
        }

      --len;
    }
}

#define INDENT SB \
  if (enc->flags & F_INDENT)            \
    {                                   \
      int i_;                           \
      need (enc, enc->indent);          \
      for (i_ = enc->indent * 3; i_--; )\
        encode_ch (enc, ' ');           \
    }                                   \
  SE

#define SPACE SB need (enc, 1); encode_ch (enc, ' '); SE
#define NL    SB if (enc->flags & F_INDENT) { need (enc, 1); encode_ch (enc, '\n'); } SE
#define COMMA SB \
  encode_ch (enc, ',');                 \
  if (enc->flags & F_INDENT)            \
    NL;                                 \
  else if (enc->flags & F_SPACE_AFTER)  \
    SPACE;                              \
  SE

static void encode_sv (enc_t *enc, SV *sv);

static void
encode_av (enc_t *enc, AV *av)
{
  int i, len = av_len (av);

  encode_ch (enc, '['); NL;
  ++enc->indent;

  for (i = 0; i <= len; ++i)
    {
      INDENT;
      encode_sv (enc, *av_fetch (av, i, 0));

      if (i < len)
        COMMA;
    }

  NL;

  --enc->indent;
  INDENT; encode_ch (enc, ']');
}

static void
encode_he (enc_t *enc, HE *he)
{
  encode_ch (enc, '"');

  if (HeKLEN (he) == HEf_SVKEY)
    {
      SV *sv = HeSVKEY (he);
      STRLEN len;
      char *str = SvPV (sv, len);

      encode_str (enc, str, len, SvUTF8 (sv));
    }
  else
    encode_str (enc, HeKEY (he), HeKLEN (he), HeKUTF8 (he));

  encode_ch (enc, '"');

  if (enc->flags & F_SPACE_BEFORE) SPACE;
  encode_ch (enc, ':');
  if (enc->flags & F_SPACE_AFTER ) SPACE;
  encode_sv (enc, HeVAL (he));
}

// compare hash entries, used when all keys are bytestrings
static int
he_cmp_fast (const void *a_, const void *b_)
{
  int cmp;

  HE *a = *(HE **)a_;
  HE *b = *(HE **)b_;

  STRLEN la = HeKLEN (a);
  STRLEN lb = HeKLEN (b);

  if (!(cmp == memcmp (HeKEY (a), HeKEY (b), la < lb ? la : lb)))
    cmp = la < lb ? -1 : la == lb ? 0 : 1;

  return cmp;
}

// compare hash entries, used when some keys are sv's or utf-x
static int
he_cmp_slow (const void *a, const void *b)
{
  return sv_cmp (HeSVKEY_force (*(HE **)a), HeSVKEY_force (*(HE **)b));
}

static void
encode_hv (enc_t *enc, HV *hv)
{
  int count, i;

  encode_ch (enc, '{'); NL; ++enc->indent;

  if ((count = hv_iterinit (hv)))
    {
      // for canonical output we have to sort by keys first
      // actually, this is mostly due to the stupid so-called
      // security workaround added somewhere in 5.8.x.
      // that randomises hash orderings
      if (enc->flags & F_CANONICAL)
        {
          HE *he, *hes [count];
          int fast = 1;

          i = 0;
          while ((he = hv_iternext (hv)))
            {
              hes [i++] = he;
              if (HeKLEN (he) < 0 || HeKUTF8 (he))
                fast = 0;
            }

          assert (i == count);

          if (fast)
            qsort (hes, count, sizeof (HE *), he_cmp_fast);
          else
            {
              // hack to disable "use bytes"
              COP *oldcop = PL_curcop, cop;
              cop.op_private = 0;
              PL_curcop = &cop;

              SAVETMPS;
              qsort (hes, count, sizeof (HE *), he_cmp_slow);
              FREETMPS;

              PL_curcop = oldcop;
            }

          for (i = 0; i < count; ++i)
            {
              INDENT;
              encode_he (enc, hes [i]);

              if (i < count - 1)
                COMMA;
            }

          NL;
        }
      else
        {
          SV *sv;
          HE *he = hv_iternext (hv);

          for (;;)
            {
              INDENT;
              encode_he (enc, he);

              if (!(he = hv_iternext (hv)))
                break;

              COMMA;
            }

          NL;
        }
    }

  --enc->indent; INDENT; encode_ch (enc, '}');
}

static void
encode_sv (enc_t *enc, SV *sv)
{
  if (SvPOKp (sv))
    {
      STRLEN len;
      char *str = SvPV (sv, len);
      encode_ch (enc, '"');
      encode_str (enc, str, len, SvUTF8 (sv));
      encode_ch (enc, '"');
    }
  else if (SvNOKp (sv))
    {
      need (enc, NV_DIG + 32);
      Gconvert (SvNVX (sv), NV_DIG, 0, enc->cur);
      enc->cur += strlen (enc->cur);
    }
  else if (SvIOKp (sv))
    {
      need (enc, 64);
      enc->cur += 
         SvIsUV(sv)
            ? snprintf (enc->cur, 64, "%"UVuf, (UV)SvUVX (sv))
            : snprintf (enc->cur, 64, "%"IVdf, (IV)SvIVX (sv));
    }
  else if (SvROK (sv))
    {
      if (!--enc->max_recurse)
        croak ("data structure too deep (hit recursion limit)");

      sv = SvRV (sv);

      switch (SvTYPE (sv))
        {
          case SVt_PVAV: encode_av (enc, (AV *)sv); break;
          case SVt_PVHV: encode_hv (enc, (HV *)sv); break;

          default:
            croak ("JSON can only represent references to arrays or hashes");
        }
    }
  else if (!SvOK (sv))
    encode_str (enc, "null", 4, 0);
  else
    croak ("encountered perl type that JSON cannot handle");
}

static SV *
encode_json (SV *scalar, UV flags)
{
  enc_t enc;
  enc.flags       = flags;
  enc.sv          = sv_2mortal (NEWSV (0, INIT_SIZE));
  enc.cur         = SvPVX (enc.sv);
  enc.end         = SvEND (enc.sv);
  enc.max_recurse = 0;
  enc.indent      = 0;

  SvPOK_only (enc.sv);
  encode_sv (&enc, scalar);

  if (!(flags & (F_ASCII | F_UTF8)))
    SvUTF8_on (enc.sv);

  SvCUR_set (enc.sv, enc.cur - SvPVX (enc.sv));
  return enc.sv;
}

/////////////////////////////////////////////////////////////////////////////

#define WS \
  for (;;)                              \
    {                                   \
      char ch = *dec->cur;              \
      if (ch > 0x20                     \
          || (ch != 0x20 && ch != 0x0a && ch != 0x0d && ch != 0x09)) \
        break;                          \
      ++dec->cur;                       \
    }

#define ERR(reason) SB dec->err = reason; goto fail; SE
#define EXPECT_CH(ch) SB \
  if (*dec->cur != ch)          \
    ERR (# ch " expected");     \
  ++dec->cur;                   \
  SE

static SV *decode_sv (dec_t *dec);

#define APPEND_CH(ch) SB \
  SvGROW (sv, cur + 1 + 1);     \
  SvPVX (sv)[cur++] = (ch);     \
  SE

static signed char decode_hexdigit[256];

static UV
decode_4hex (dec_t *dec)
{
  signed char d1, d2, d3, d4;

  d1 = decode_hexdigit [((unsigned char *)dec->cur) [0]];
  if (d1 < 0) ERR ("four hexadecimal digits expected");
  d2 = decode_hexdigit [((unsigned char *)dec->cur) [1]];
  if (d2 < 0) ERR ("four hexadecimal digits expected");
  d3 = decode_hexdigit [((unsigned char *)dec->cur) [2]];
  if (d3 < 0) ERR ("four hexadecimal digits expected");
  d4 = decode_hexdigit [((unsigned char *)dec->cur) [3]];
  if (d4 < 0) ERR ("four hexadecimal digits expected");

  dec->cur += 4;

  return ((UV)d1) << 12
       | ((UV)d2) <<  8
       | ((UV)d3) <<  4
       | ((UV)d4);

fail:
  return (UV)-1;
}

static SV *
decode_str (dec_t *dec)
{
  SV *sv = NEWSV (0,2);
  STRLEN cur = 0;
  int utf8 = 0;

  for (;;)
    {
      unsigned char ch = *(unsigned char *)dec->cur;

      if (ch == '"')
        break;
      else if (ch == '\\')
        {
          switch (*++dec->cur)
            {
              case '\\':
              case '/':
              case '"': APPEND_CH (*dec->cur++); break;

              case 'b': APPEND_CH ('\010'); ++dec->cur; break;
              case 't': APPEND_CH ('\011'); ++dec->cur; break;
              case 'n': APPEND_CH ('\012'); ++dec->cur; break;
              case 'f': APPEND_CH ('\014'); ++dec->cur; break;
              case 'r': APPEND_CH ('\015'); ++dec->cur; break;

              case 'u':
                {
                  UV lo, hi;
                  ++dec->cur;

                  hi = decode_4hex (dec);
                  if (hi == (UV)-1)
                    goto fail;

                  // possibly a surrogate pair
                  if (hi >= 0xd800 && hi < 0xdc00)
                    {
                      if (dec->cur [0] != '\\' || dec->cur [1] != 'u')
                        ERR ("illegal surrogate character");

                      dec->cur += 2;

                      lo = decode_4hex (dec);
                      if (lo == (UV)-1)
                        goto fail;

                      if (lo < 0xdc00 || lo >= 0xe000)
                        ERR ("surrogate pair expected");

                      hi = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000;
                    }
                  else if (lo >= 0xdc00 && lo < 0xe000)
                    ERR ("illegal surrogate character");

                  if (hi >= 0x80)
                    {
                      utf8 = 1;

                      SvGROW (sv, cur + 4 + 1); // at most 4 bytes for 21 bits
                      cur = (char *)uvuni_to_utf8_flags (SvPVX (sv) + cur, hi, 0) - SvPVX (sv);
                    }
                  else
                    APPEND_CH (hi);
                }
                break;
            }
        }
      else if (ch >= 0x20 && ch <= 0x7f)
        APPEND_CH (*dec->cur++);
      else if (ch >= 0x80)
        {
          STRLEN clen;
          UV uch = utf8n_to_uvuni (dec->cur, dec->end - dec->cur, &clen, UTF8_CHECK_ONLY);
          if (clen < 0)
            ERR ("malformed UTF-8 character in string, cannot convert to JSON");

          SvGROW (sv, cur + clen + 1); // at most 4 bytes for 21 bits
          memcpy (SvPVX (sv) + cur, dec->cur, clen);
          dec->cur += clen;
        }
      else
        ERR ("invalid character encountered");
    }

  ++dec->cur;

  SvPOK_only (sv);

  SvCUR_set (sv, cur);
  *SvEND (sv) = 0;

  if (utf8)
    SvUTF8_on (sv);

  return sv;

fail:
  SvREFCNT_dec (sv);
  return 0;
}

static SV *
decode_num (dec_t *dec)
{
  int is_nv = 0;
  char *start = dec->cur;

  // [minus]
  if (*dec->cur == '-')
    ++dec->cur;

  if (*dec->cur == '0')
    {
      ++dec->cur;
      if (*dec->cur >= '0' && *dec->cur <= '9')
         ERR ("malformed number (leading zero must not be followed by another digit)");
    }

  // int
  while (*dec->cur >= '0' && *dec->cur <= '9')
    ++dec->cur;

  // [frac]
  if (*dec->cur == '.')
    {
      is_nv = 1;

      do
        {
          ++dec->cur;
        }
      while (*dec->cur >= '0' && *dec->cur <= '9');
    }

  // [exp]
  if (*dec->cur == 'e' || *dec->cur == 'E')
    {
      is_nv = 1;

      ++dec->cur;
      if (*dec->cur == '-' || *dec->cur == '+')
        ++dec->cur;

      while (*dec->cur >= '0' && *dec->cur <= '9')
        ++dec->cur;
    }

  if (!is_nv)
    {
      UV uv;
      int numtype = grok_number (start, dec->cur - start, &uv);
      if (numtype & IS_NUMBER_IN_UV)
        if (numtype & IS_NUMBER_NEG)
          {
            if (uv < (UV)IV_MIN)
              return newSViv (-(IV)uv);
          }
        else
          return newSVuv (uv);
    }

  return newSVnv (Atof (start));

fail:
  return 0;
}

static SV *
decode_av (dec_t *dec)
{
  AV *av = newAV ();

  for (;;)
    {
      SV *value;

      value = decode_sv (dec);
      if (!value)
        goto fail;

      av_push (av, value);

      WS;

      if (*dec->cur == ']')
        {
          ++dec->cur;
          break;
        }
      
      if (*dec->cur != ',')
        ERR (", or ] expected while parsing array");

      ++dec->cur;
    }

  return newRV_noinc ((SV *)av);

fail:
  SvREFCNT_dec (av);
  return 0;
}

static SV *
decode_hv (dec_t *dec)
{
  HV *hv = newHV ();

  for (;;)
    {
      SV *key, *value;

      WS; EXPECT_CH ('"');

      key = decode_str (dec);
      if (!key)
        goto fail;

      WS; EXPECT_CH (':');

      value = decode_sv (dec);
      if (!value)
        {
          SvREFCNT_dec (key);
          goto fail;
        }

      //TODO: optimise
      hv_store_ent (hv, key, value, 0);

      WS;

      if (*dec->cur == '}')
        {
          ++dec->cur;
          break;
        }

      if (*dec->cur != ',')
        ERR (", or } expected while parsing object/hash");

      ++dec->cur;
    }

  return newRV_noinc ((SV *)hv);

fail:
  SvREFCNT_dec (hv);
  return 0;
}

static SV *
decode_sv (dec_t *dec)
{
  WS;
  switch (*dec->cur)
    {
      case '"': ++dec->cur; return decode_str (dec); 
      case '[': ++dec->cur; return decode_av (dec); 
      case '{': ++dec->cur; return decode_hv (dec);

      case '-':
      case '0': case '1': case '2': case '3': case '4':
      case '5': case '6': case '7': case '8': case '9':
        return decode_num (dec);

      case 't':
        if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "true", 4))
          {
            dec->cur += 4;
            return newSViv (1);
          }
        else
          ERR ("'true' expected");

        break;

      case 'f':
        if (dec->end - dec->cur >= 5 && !memcmp (dec->cur, "false", 5))
          {
            dec->cur += 5;
            return newSViv (0);
          }
        else
          ERR ("'false' expected");

        break;

      case 'n':
        if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "null", 4))
          {
            dec->cur += 4;
            return newSViv (1);
          }
        else
          ERR ("'null' expected");

        break;

      default:
        ERR ("malformed json string");
        break;
    }

fail:
  return 0;
}

static SV *
decode_json (SV *string, UV flags)
{
  SV *sv;

  if (!(flags & F_UTF8))
    sv_utf8_upgrade (string);

  SvGROW (string, SvCUR (string) + 1); // should basically be a NOP

  dec_t dec;
  dec.flags = flags;
  dec.cur   = SvPVX (string);
  dec.end   = SvEND (string);
  dec.err   = 0;

  *dec.end = 1; // invalid anywhere
  sv = decode_sv (&dec);
  *dec.end = 0;

  if (!sv)
    {
      IV offset = utf8_distance (dec.cur, SvPVX (string));
      SV *uni = sv_newmortal ();

      pv_uni_display (uni, dec.cur, dec.end - dec.cur, 20, UNI_DISPLAY_QQ);
      croak ("%s, at character %d (%s)",
             dec.err,
             (int)offset,
             dec.cur != dec.end ? SvPV_nolen (uni) : "(end of string)");
    }

  sv_dump (sv);//D
  return sv_2mortal (sv);
}

MODULE = JSON::XS               PACKAGE = JSON::XS

BOOT:
{
        int i;

        memset (decode_hexdigit, 0xff, 256);
        for (i = 10; i--; )
          decode_hexdigit ['0' + i] = i;

        for (i = 6; --i; )
          {
            decode_hexdigit ['a' + i] = 10 + i;
            decode_hexdigit ['A' + i] = 10 + i;
          }

        json_stash = gv_stashpv ("JSON::XS", 1);
}

SV *new (char *dummy)
        CODE:
        RETVAL = sv_bless (newRV_noinc (newSVuv (F_DEFAULT)), json_stash);
        OUTPUT:
        RETVAL

SV *ascii (SV *self, int enable)
        ALIAS:
        ascii        = F_ASCII
        utf8         = F_UTF8
        indent       = F_INDENT
        canonical    = F_CANONICAL
        space_before = F_SPACE_BEFORE
        space_after  = F_SPACE_AFTER
        json_rpc     = F_JSON_RPC
        pretty       = F_PRETTY
        CODE:
{
        UV *uv = SvJSON (self);
        if (enable)
          *uv |=  ix;
        else
          *uv &= ~ix;

        RETVAL = newSVsv (self);
}
        OUTPUT:
        RETVAL

void encode (SV *self, SV *scalar)
        PPCODE:
        XPUSHs (encode_json (scalar, *SvJSON (self)));

void decode (SV *self, SV *jsonstr)
        PPCODE:
        XPUSHs (decode_json (jsonstr, *SvJSON (self)));

void to_json (SV *scalar)
        PPCODE:
        XPUSHs (encode_json (scalar, F_UTF8));

void from_json (SV *jsonstr)
        PPCODE:
        XPUSHs (decode_json (jsonstr, F_UTF8));

Revision:	1.2
Committed:	Thu Mar 22 17:28:50 2007 UTC (17 years, 2 months ago) by root
Branch:	MAIN
Changes since 1.1:	+13 -3 lines
Log Message:	added preliminary documentation
#	User	Rev	Content
1	root	1.1	#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
9			#define F_ASCII 0x00000001
10			#define F_UTF8 0x00000002
11			#define F_INDENT 0x00000004
12			#define F_CANONICAL 0x00000008
13			#define F_SPACE_BEFORE 0x00000010
14			#define F_SPACE_AFTER 0x00000020
15			#define F_JSON_RPC 0x00000040
16
17	root	1.2	#define F_PRETTY F_INDENT \| F_SPACE_BEFORE \| F_SPACE_AFTER
18	root	1.1	#define F_DEFAULT 0
19
20			#define INIT_SIZE 32 // initial scalar size to be allocated
21
22			#define SB do {
23			#define SE } while (0)
24
25			static HV *json_stash;
26
27			// structure used for encoding JSON
28			typedef struct
29			{
30			char *cur;
31			STRLEN len; // SvLEN (sv)
32			char *end; // SvEND (sv)
33			SV *sv;
34			UV flags;
35			int max_recurse;
36			int indent;
37			} enc_t;
38
39			// structure used for decoding JSON
40			typedef struct
41			{
42			char *cur;
43			char *end;
44			char *err;
45			UV flags;
46			} dec_t;
47
48			static UV *
49			SvJSON (SV *sv)
50			{
51			if (!(SvROK (sv) && SvOBJECT (SvRV (sv)) && SvSTASH (SvRV (sv)) == json_stash))
52			croak ("object is not of type JSON::XS");
53
54			return &SvUVX (SvRV (sv));
55			}
56
57			/////////////////////////////////////////////////////////////////////////////
58
59			static void
60			need (enc_t *enc, STRLEN len)
61			{
62			if (enc->cur + len >= enc->end)
63			{
64			STRLEN cur = enc->cur - SvPVX (enc->sv);
65			SvGROW (enc->sv, cur + len + 1);
66			enc->cur = SvPVX (enc->sv) + cur;
67			enc->end = SvEND (enc->sv);
68			}
69			}
70
71			static void
72			encode_ch (enc_t *enc, char ch)
73			{
74			need (enc, 1);
75			*enc->cur++ = ch;
76			}
77
78			static void
79			encode_str (enc_t enc, char str, STRLEN len, int is_utf8)
80			{
81			char *end = str + len;
82
83			while (str < end)
84			{
85			unsigned char ch = (unsigned char )str;
86			if (ch >= 0x20 && ch < 0x80) // most common case
87			{
88			*enc->cur++ = ch;
89			str++;
90			}
91			else
92			{
93			STRLEN clen;
94			UV uch;
95
96			if (is_utf8)
97			{
98			uch = utf8n_to_uvuni (str, end - str, &clen, UTF8_CHECK_ONLY);
99			if (clen < 0)
100			croak ("malformed UTF-8 character in string, cannot convert to JSON");
101			}
102			else
103			{
104			uch = ch;
105			clen = 1;
106			}
107
108			need (enc, len += 6);
109
110			if (uch < 0xa0 \|\| enc->flags & F_ASCII)
111			{
112			if (uch > 0xFFFFUL)
113			{
114			len += 6;
115			need (enc, len += 6);
116			sprintf (enc->cur, "\\u%04x\\u%04x",
117			(uch - 0x10000) / 0x400 + 0xD800,
118			(uch - 0x10000) % 0x400 + 0xDC00);
119			enc->cur += 12;
120			}
121			else
122			{
123			sprintf (enc->cur, "\\u%04x", uch);
124			enc->cur += 6;
125			}
126			}
127			else if (is_utf8)
128			{
129			memcpy (enc->cur, str, clen);
130			enc->cur += clen;
131			}
132			else
133			enc->cur = uvuni_to_utf8_flags (enc->cur, uch, 0);
134
135			str += clen;
136			}
137
138			--len;
139			}
140			}
141
142			#define INDENT SB \
143			if (enc->flags & F_INDENT) \
144			{ \
145			int i_; \
146			need (enc, enc->indent); \
147			for (i_ = enc->indent * 3; i_--; )\
148			encode_ch (enc, ' '); \
149			} \
150			SE
151
152	root	1.2	#define SPACE SB need (enc, 1); encode_ch (enc, ' '); SE
153	root	1.1	#define NL SB if (enc->flags & F_INDENT) { need (enc, 1); encode_ch (enc, '\n'); } SE
154			#define COMMA SB \
155			encode_ch (enc, ','); \
156			if (enc->flags & F_INDENT) \
157			NL; \
158			else if (enc->flags & F_SPACE_AFTER) \
159			SPACE; \
160			SE
161
162			static void encode_sv (enc_t enc, SV sv);
163
164			static void
165			encode_av (enc_t enc, AV av)
166			{
167			int i, len = av_len (av);
168
169			encode_ch (enc, '['); NL;
170			++enc->indent;
171
172			for (i = 0; i <= len; ++i)
173			{
174			INDENT;
175			encode_sv (enc, *av_fetch (av, i, 0));
176
177			if (i < len)
178			COMMA;
179			}
180
181			NL;
182
183			--enc->indent;
184			INDENT; encode_ch (enc, ']');
185			}
186
187			static void
188			encode_he (enc_t enc, HE he)
189			{
190			encode_ch (enc, '"');
191
192			if (HeKLEN (he) == HEf_SVKEY)
193			{
194			SV *sv = HeSVKEY (he);
195			STRLEN len;
196			char *str = SvPV (sv, len);
197
198			encode_str (enc, str, len, SvUTF8 (sv));
199			}
200			else
201			encode_str (enc, HeKEY (he), HeKLEN (he), HeKUTF8 (he));
202
203			encode_ch (enc, '"');
204
205			if (enc->flags & F_SPACE_BEFORE) SPACE;
206			encode_ch (enc, ':');
207			if (enc->flags & F_SPACE_AFTER ) SPACE;
208			encode_sv (enc, HeVAL (he));
209			}
210
211			// compare hash entries, used when all keys are bytestrings
212			static int
213			he_cmp_fast (const void a_, const void b_)
214			{
215			int cmp;
216
217			HE a = (HE **)a_;
218			HE b = (HE **)b_;
219
220			STRLEN la = HeKLEN (a);
221			STRLEN lb = HeKLEN (b);
222
223			if (!(cmp == memcmp (HeKEY (a), HeKEY (b), la < lb ? la : lb)))
224			cmp = la < lb ? -1 : la == lb ? 0 : 1;
225
226			return cmp;
227			}
228
229			// compare hash entries, used when some keys are sv's or utf-x
230			static int
231			he_cmp_slow (const void a, const void b)
232			{
233			return sv_cmp (HeSVKEY_force ((HE )a), HeSVKEY_force ((HE **)b));
234			}
235
236			static void
237			encode_hv (enc_t enc, HV hv)
238			{
239			int count, i;
240
241			encode_ch (enc, '{'); NL; ++enc->indent;
242
243			if ((count = hv_iterinit (hv)))
244			{
245			// for canonical output we have to sort by keys first
246			// actually, this is mostly due to the stupid so-called
247			// security workaround added somewhere in 5.8.x.
248			// that randomises hash orderings
249			if (enc->flags & F_CANONICAL)
250			{
251			HE he, hes [count];
252			int fast = 1;
253
254			i = 0;
255			while ((he = hv_iternext (hv)))
256			{
257			hes [i++] = he;
258			if (HeKLEN (he) < 0 \|\| HeKUTF8 (he))
259			fast = 0;
260			}
261
262			assert (i == count);
263
264			if (fast)
265			qsort (hes, count, sizeof (HE *), he_cmp_fast);
266			else
267			{
268			// hack to disable "use bytes"
269			COP *oldcop = PL_curcop, cop;
270			cop.op_private = 0;
271			PL_curcop = &cop;
272
273			SAVETMPS;
274			qsort (hes, count, sizeof (HE *), he_cmp_slow);
275			FREETMPS;
276
277			PL_curcop = oldcop;
278			}
279
280			for (i = 0; i < count; ++i)
281			{
282			INDENT;
283			encode_he (enc, hes [i]);
284
285			if (i < count - 1)
286			COMMA;
287			}
288
289			NL;
290			}
291			else
292			{
293			SV *sv;
294			HE *he = hv_iternext (hv);
295
296			for (;;)
297			{
298			INDENT;
299			encode_he (enc, he);
300
301			if (!(he = hv_iternext (hv)))
302			break;
303
304			COMMA;
305			}
306
307			NL;
308			}
309			}
310
311			--enc->indent; INDENT; encode_ch (enc, '}');
312			}
313
314			static void
315			encode_sv (enc_t enc, SV sv)
316			{
317			if (SvPOKp (sv))
318			{
319			STRLEN len;
320			char *str = SvPV (sv, len);
321			encode_ch (enc, '"');
322			encode_str (enc, str, len, SvUTF8 (sv));
323			encode_ch (enc, '"');
324			}
325			else if (SvNOKp (sv))
326			{
327			need (enc, NV_DIG + 32);
328			Gconvert (SvNVX (sv), NV_DIG, 0, enc->cur);
329			enc->cur += strlen (enc->cur);
330			}
331			else if (SvIOKp (sv))
332			{
333			need (enc, 64);
334			enc->cur +=
335			SvIsUV(sv)
336			? snprintf (enc->cur, 64, "%"UVuf, (UV)SvUVX (sv))
337			: snprintf (enc->cur, 64, "%"IVdf, (IV)SvIVX (sv));
338			}
339			else if (SvROK (sv))
340			{
341			if (!--enc->max_recurse)
342			croak ("data structure too deep (hit recursion limit)");
343
344			sv = SvRV (sv);
345
346			switch (SvTYPE (sv))
347			{
348			case SVt_PVAV: encode_av (enc, (AV *)sv); break;
349			case SVt_PVHV: encode_hv (enc, (HV *)sv); break;
350
351			default:
352			croak ("JSON can only represent references to arrays or hashes");
353			}
354			}
355			else if (!SvOK (sv))
356			encode_str (enc, "null", 4, 0);
357			else
358			croak ("encountered perl type that JSON cannot handle");
359			}
360
361			static SV *
362			encode_json (SV *scalar, UV flags)
363			{
364			enc_t enc;
365			enc.flags = flags;
366			enc.sv = sv_2mortal (NEWSV (0, INIT_SIZE));
367			enc.cur = SvPVX (enc.sv);
368			enc.end = SvEND (enc.sv);
369			enc.max_recurse = 0;
370			enc.indent = 0;
371
372			SvPOK_only (enc.sv);
373			encode_sv (&enc, scalar);
374
375			if (!(flags & (F_ASCII \| F_UTF8)))
376			SvUTF8_on (enc.sv);
377
378			SvCUR_set (enc.sv, enc.cur - SvPVX (enc.sv));
379			return enc.sv;
380			}
381
382			/////////////////////////////////////////////////////////////////////////////
383
384			#define WS \
385			for (;;) \
386			{ \
387			char ch = *dec->cur; \
388			if (ch > 0x20 \
389			\|\| (ch != 0x20 && ch != 0x0a && ch != 0x0d && ch != 0x09)) \
390			break; \
391			++dec->cur; \
392			}
393
394			#define ERR(reason) SB dec->err = reason; goto fail; SE
395			#define EXPECT_CH(ch) SB \
396			if (*dec->cur != ch) \
397			ERR (# ch " expected"); \
398			++dec->cur; \
399			SE
400
401			static SV decode_sv (dec_t dec);
402
403			#define APPEND_CH(ch) SB \
404			SvGROW (sv, cur + 1 + 1); \
405			SvPVX (sv)[cur++] = (ch); \
406			SE
407
408			static signed char decode_hexdigit[256];
409
410			static UV
411			decode_4hex (dec_t *dec)
412			{
413			signed char d1, d2, d3, d4;
414
415			d1 = decode_hexdigit [((unsigned char *)dec->cur) [0]];
416			if (d1 < 0) ERR ("four hexadecimal digits expected");
417			d2 = decode_hexdigit [((unsigned char *)dec->cur) [1]];
418			if (d2 < 0) ERR ("four hexadecimal digits expected");
419			d3 = decode_hexdigit [((unsigned char *)dec->cur) [2]];
420			if (d3 < 0) ERR ("four hexadecimal digits expected");
421			d4 = decode_hexdigit [((unsigned char *)dec->cur) [3]];
422			if (d4 < 0) ERR ("four hexadecimal digits expected");
423
424			dec->cur += 4;
425
426			return ((UV)d1) << 12
427			\| ((UV)d2) << 8
428			\| ((UV)d3) << 4
429			\| ((UV)d4);
430
431			fail:
432			return (UV)-1;
433			}
434
435			static SV *
436			decode_str (dec_t *dec)
437			{
438			SV *sv = NEWSV (0,2);
439			STRLEN cur = 0;
440			int utf8 = 0;
441
442			for (;;)
443			{
444			unsigned char ch = (unsigned char )dec->cur;
445
446			if (ch == '"')
447			break;
448			else if (ch == '\\')
449			{
450			switch (*++dec->cur)
451			{
452			case '\\':
453			case '/':
454			case '"': APPEND_CH (*dec->cur++); break;
455
456			case 'b': APPEND_CH ('\010'); ++dec->cur; break;
457			case 't': APPEND_CH ('\011'); ++dec->cur; break;
458			case 'n': APPEND_CH ('\012'); ++dec->cur; break;
459			case 'f': APPEND_CH ('\014'); ++dec->cur; break;
460			case 'r': APPEND_CH ('\015'); ++dec->cur; break;
461
462			case 'u':
463			{
464			UV lo, hi;
465			++dec->cur;
466
467			hi = decode_4hex (dec);
468			if (hi == (UV)-1)
469			goto fail;
470
471			// possibly a surrogate pair
472			if (hi >= 0xd800 && hi < 0xdc00)
473			{
474			if (dec->cur [0] != '\\' \|\| dec->cur [1] != 'u')
475			ERR ("illegal surrogate character");
476
477			dec->cur += 2;
478
479			lo = decode_4hex (dec);
480			if (lo == (UV)-1)
481			goto fail;
482
483			if (lo < 0xdc00 \|\| lo >= 0xe000)
484			ERR ("surrogate pair expected");
485
486			hi = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000;
487			}
488			else if (lo >= 0xdc00 && lo < 0xe000)
489			ERR ("illegal surrogate character");
490
491			if (hi >= 0x80)
492			{
493			utf8 = 1;
494
495			SvGROW (sv, cur + 4 + 1); // at most 4 bytes for 21 bits
496			cur = (char *)uvuni_to_utf8_flags (SvPVX (sv) + cur, hi, 0) - SvPVX (sv);
497			}
498			else
499			APPEND_CH (hi);
500			}
501			break;
502			}
503			}
504			else if (ch >= 0x20 && ch <= 0x7f)
505			APPEND_CH (*dec->cur++);
506			else if (ch >= 0x80)
507			{
508			STRLEN clen;
509			UV uch = utf8n_to_uvuni (dec->cur, dec->end - dec->cur, &clen, UTF8_CHECK_ONLY);
510			if (clen < 0)
511			ERR ("malformed UTF-8 character in string, cannot convert to JSON");
512
513			SvGROW (sv, cur + clen + 1); // at most 4 bytes for 21 bits
514			memcpy (SvPVX (sv) + cur, dec->cur, clen);
515			dec->cur += clen;
516			}
517			else
518			ERR ("invalid character encountered");
519			}
520
521			++dec->cur;
522
523			SvPOK_only (sv);
524
525			SvCUR_set (sv, cur);
526			*SvEND (sv) = 0;
527
528			if (utf8)
529			SvUTF8_on (sv);
530
531			return sv;
532
533			fail:
534			SvREFCNT_dec (sv);
535			return 0;
536			}
537
538			static SV *
539			decode_num (dec_t *dec)
540			{
541			int is_nv = 0;
542			char *start = dec->cur;
543
544			// [minus]
545			if (*dec->cur == '-')
546			++dec->cur;
547
548			if (*dec->cur == '0')
549			{
550			++dec->cur;
551			if (dec->cur >= '0' && dec->cur <= '9')
552			ERR ("malformed number (leading zero must not be followed by another digit)");
553			}
554
555			// int
556			while (dec->cur >= '0' && dec->cur <= '9')
557			++dec->cur;
558
559			// [frac]
560			if (*dec->cur == '.')
561			{
562			is_nv = 1;
563
564			do
565			{
566			++dec->cur;
567			}
568			while (dec->cur >= '0' && dec->cur <= '9');
569			}
570
571			// [exp]
572			if (dec->cur == 'e' \|\| dec->cur == 'E')
573			{
574			is_nv = 1;
575
576			++dec->cur;
577			if (dec->cur == '-' \|\| dec->cur == '+')
578			++dec->cur;
579
580			while (dec->cur >= '0' && dec->cur <= '9')
581			++dec->cur;
582			}
583
584			if (!is_nv)
585			{
586			UV uv;
587			int numtype = grok_number (start, dec->cur - start, &uv);
588			if (numtype & IS_NUMBER_IN_UV)
589			if (numtype & IS_NUMBER_NEG)
590			{
591			if (uv < (UV)IV_MIN)
592			return newSViv (-(IV)uv);
593			}
594			else
595			return newSVuv (uv);
596			}
597
598			return newSVnv (Atof (start));
599
600			fail:
601			return 0;
602			}
603
604			static SV *
605			decode_av (dec_t *dec)
606			{
607			AV *av = newAV ();
608
609			for (;;)
610			{
611			SV *value;
612
613			value = decode_sv (dec);
614			if (!value)
615			goto fail;
616
617			av_push (av, value);
618
619			WS;
620
621			if (*dec->cur == ']')
622			{
623			++dec->cur;
624			break;
625			}
626
627			if (*dec->cur != ',')
628			ERR (", or ] expected while parsing array");
629
630			++dec->cur;
631			}
632
633			return newRV_noinc ((SV *)av);
634
635			fail:
636			SvREFCNT_dec (av);
637			return 0;
638			}
639
640			static SV *
641			decode_hv (dec_t *dec)
642			{
643			HV *hv = newHV ();
644
645			for (;;)
646			{
647			SV key, value;
648
649			WS; EXPECT_CH ('"');
650
651			key = decode_str (dec);
652			if (!key)
653			goto fail;
654
655			WS; EXPECT_CH (':');
656
657			value = decode_sv (dec);
658			if (!value)
659			{
660			SvREFCNT_dec (key);
661			goto fail;
662			}
663
664			//TODO: optimise
665			hv_store_ent (hv, key, value, 0);
666
667			WS;
668
669			if (*dec->cur == '}')
670			{
671			++dec->cur;
672			break;
673			}
674
675			if (*dec->cur != ',')
676			ERR (", or } expected while parsing object/hash");
677
678			++dec->cur;
679			}
680
681			return newRV_noinc ((SV *)hv);
682
683			fail:
684			SvREFCNT_dec (hv);
685			return 0;
686			}
687
688			static SV *
689			decode_sv (dec_t *dec)
690			{
691			WS;
692			switch (*dec->cur)
693			{
694			case '"': ++dec->cur; return decode_str (dec);
695			case '[': ++dec->cur; return decode_av (dec);
696			case '{': ++dec->cur; return decode_hv (dec);
697
698			case '-':
699			case '0': case '1': case '2': case '3': case '4':
700			case '5': case '6': case '7': case '8': case '9':
701			return decode_num (dec);
702
703			case 't':
704			if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "true", 4))
705			{
706			dec->cur += 4;
707			return newSViv (1);
708			}
709			else
710			ERR ("'true' expected");
711
712			break;
713
714			case 'f':
715			if (dec->end - dec->cur >= 5 && !memcmp (dec->cur, "false", 5))
716			{
717			dec->cur += 5;
718			return newSViv (0);
719			}
720			else
721			ERR ("'false' expected");
722
723			break;
724
725			case 'n':
726			if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "null", 4))
727			{
728			dec->cur += 4;
729			return newSViv (1);
730			}
731			else
732			ERR ("'null' expected");
733
734			break;
735
736			default:
737			ERR ("malformed json string");
738			break;
739			}
740
741			fail:
742			return 0;
743			}
744
745			static SV *
746			decode_json (SV *string, UV flags)
747			{
748			SV *sv;
749
750			if (!(flags & F_UTF8))
751			sv_utf8_upgrade (string);
752
753			SvGROW (string, SvCUR (string) + 1); // should basically be a NOP
754
755			dec_t dec;
756			dec.flags = flags;
757			dec.cur = SvPVX (string);
758			dec.end = SvEND (string);
759			dec.err = 0;
760
761			*dec.end = 1; // invalid anywhere
762			sv = decode_sv (&dec);
763			*dec.end = 0;
764
765			if (!sv)
766			{
767			IV offset = utf8_distance (dec.cur, SvPVX (string));
768			SV *uni = sv_newmortal ();
769
770			pv_uni_display (uni, dec.cur, dec.end - dec.cur, 20, UNI_DISPLAY_QQ);
771			croak ("%s, at character %d (%s)",
772			dec.err,
773			(int)offset,
774			dec.cur != dec.end ? SvPV_nolen (uni) : "(end of string)");
775			}
776
777			sv_dump (sv);//D
778			return sv_2mortal (sv);
779			}
780
781			MODULE = JSON::XS PACKAGE = JSON::XS
782
783			BOOT:
784			{
785			int i;
786
787			memset (decode_hexdigit, 0xff, 256);
788			for (i = 10; i--; )
789			decode_hexdigit ['0' + i] = i;
790
791			for (i = 6; --i; )
792			{
793			decode_hexdigit ['a' + i] = 10 + i;
794			decode_hexdigit ['A' + i] = 10 + i;
795			}
796
797			json_stash = gv_stashpv ("JSON::XS", 1);
798			}
799
800			SV new (char dummy)
801			CODE:
802			RETVAL = sv_bless (newRV_noinc (newSVuv (F_DEFAULT)), json_stash);
803			OUTPUT:
804			RETVAL
805
806			SV ascii (SV self, int enable)
807			ALIAS:
808			ascii = F_ASCII
809			utf8 = F_UTF8
810			indent = F_INDENT
811			canonical = F_CANONICAL
812			space_before = F_SPACE_BEFORE
813			space_after = F_SPACE_AFTER
814			json_rpc = F_JSON_RPC
815	root	1.2	pretty = F_PRETTY
816	root	1.1	CODE:
817			{
818			UV *uv = SvJSON (self);
819			if (enable)
820			*uv \|= ix;
821			else
822			*uv &= ~ix;
823
824			RETVAL = newSVsv (self);
825			}
826			OUTPUT:
827			RETVAL
828
829			void encode (SV self, SV scalar)
830			PPCODE:
831			XPUSHs (encode_json (scalar, *SvJSON (self)));
832
833	root	1.2	void decode (SV self, SV jsonstr)
834	root	1.1	PPCODE:
835	root	1.2	XPUSHs (decode_json (jsonstr, *SvJSON (self)));
836
837			void to_json (SV *scalar)
838			PPCODE:
839			XPUSHs (encode_json (scalar, F_UTF8));
840
841			void from_json (SV *jsonstr)
842			PPCODE:
843			XPUSHs (decode_json (jsonstr, F_UTF8));
844	root	1.1