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_ALLOW_NONREF 0x00000080

#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;
  const 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 = SvPVX (enc->sv) + SvLEN (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;

  need (enc, len);

  while (str < end)
    {
      unsigned char ch = *(unsigned char *)str;

      if (ch == '"')
        {
          need (enc, len += 1);
          *enc->cur++ = '\\';
          *enc->cur++ = '"';
          ++str;
        }
      else if (ch == '\\')
        {
          need (enc, len += 1);
          *enc->cur++ = '\\';
          *enc->cur++ = '\\';
          ++str;
        }
      else if (ch >= 0x20 && ch < 0x80) // most common case
        {
          *enc->cur++ = ch;
          ++str;
        }
      else if (ch == '\015')
        {
          need (enc, len += 1);
          *enc->cur++ = '\\';
          *enc->cur++ = 'r';
          ++str;
        }
      else if (ch == '\012')
        {
          need (enc, len += 1);
          *enc->cur++ = '\\';
          *enc->cur++ = 'n';
          ++str;
        }
      else
        {
          STRLEN clen;
          UV uch;

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

          if (uch < 0x80 || enc->flags & F_ASCII)
            {
              if (uch > 0xFFFFUL)
                {
                  need (enc, len += 11);
                  sprintf (enc->cur, "\\u%04x\\u%04x",
                           (uch - 0x10000) / 0x400 + 0xD800,
                           (uch - 0x10000) % 0x400 + 0xDC00);
                  enc->cur += 12;
                }
              else
                {
                  static char hexdigit [16] = "0123456789abcdef";
                  need (enc, len += 5);
                  *enc->cur++ = '\\';
                  *enc->cur++ = 'u';
                  *enc->cur++ = hexdigit [ uch >> 12      ];
                  *enc->cur++ = hexdigit [(uch >>  8) & 15];
                  *enc->cur++ = hexdigit [(uch >>  4) & 15];
                  *enc->cur++ = hexdigit [(uch >>  0) & 15];
                }

              str += clen;
            }
          else if (is_utf8)
            {
              need (enc, len += clen);
              do
                {
                  *enc->cur++ = *str++;
                }
              while (--clen);
            }
          else
            {
              need (enc, 10); // never more than 11 bytes needed
              enc->cur = uvuni_to_utf8_flags (enc->cur, uch, 0);
              ++str;
            }
        }

      --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;
      
      SvGETMAGIC (sv);
      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)
{
  SvGETMAGIC (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)
{
  if (!(flags & F_ALLOW_NONREF) && !SvROK (scalar))
    croak ("hash- or arraref required (not a simple scalar, use allow_nonref to allow this)");

  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);

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;
}

#define APPEND_GROW(n) SB \
  if (cur + (n) >= end)                         \
    {                                           \
      STRLEN ofs = cur - SvPVX (sv);            \
      SvGROW (sv, ofs + (n) + 1);               \
      cur = SvPVX (sv) + ofs;                   \
      end = SvEND (sv);                         \
    }                                           \
  SE

#define APPEND_CH(ch) SB \
  APPEND_GROW (1);      \
  *cur++ = (ch);        \
  SE

static SV *
decode_str (dec_t *dec)
{
  SV *sv = NEWSV (0,2);
  int utf8 = 0;
  char *cur = SvPVX (sv);
  char *end = SvEND (sv);

  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 ("missing low surrogate character in surrogate pair");

                      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 (hi >= 0xdc00 && hi < 0xe000)
                    ERR ("missing high surrogate character in surrogate pair");

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

                      APPEND_GROW (4); // at most 4 bytes for 21 bits
                      cur = (char *)uvuni_to_utf8_flags (cur, hi, 0);
                    }
                  else
                    APPEND_CH (hi);
                }
                break;

              default:
                --dec->cur;
                ERR ("illegal backslash escape sequence in string");
            }
        }
      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 == (STRLEN)-1)
            ERR ("malformed UTF-8 character in string, cannot convert to JSON");

          APPEND_GROW (clen);
          do
            {
              *cur++ = *dec->cur++;
            }
          while (--clen);

          utf8 = 1;
        }
      else if (dec->cur == dec->end)
        ERR ("unexpected end of string while parsing json string");
      else
        ERR ("invalid character encountered");
    }

  ++dec->cur;

  SvCUR_set (sv, cur - SvPVX (sv));

  SvPOK_only (sv);
  *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)");
    }
  else if (*dec->cur < '0' || *dec->cur > '9')
    ERR ("malformed number (no digits after initial minus)");
  else
    do
      {
        ++dec->cur;
      }
    while (*dec->cur >= '0' && *dec->cur <= '9');

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

      if (*dec->cur < '0' || *dec->cur > '9')
        ERR ("malformed number (no digits after decimal point)");

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

      is_nv = 1;
    }

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

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

      if (*dec->cur < '0' || *dec->cur > '9')
        ERR ("malformed number (no digits after exp sign)");

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

      is_nv = 1;
    }

  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 ();

  WS;
  if (*dec->cur == ']')
    ++dec->cur;
  else
    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 ();

  WS;
  if (*dec->cur == '}')
    ++dec->cur;
  else
    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 newSVsv (&PL_sv_undef);
          }
        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_downgrade (string, 0);
  else
    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;

  sv = decode_sv (&dec);

  if (!sv)
    {
      IV offset = utf8_distance (dec.cur, SvPVX (string));
      SV *uni = sv_newmortal ();
      // horrible hack to silence warning inside pv_uni_display
      COP cop;
      memset (&cop, 0, sizeof (cop));
      cop.cop_warnings = pWARN_NONE;
      SAVEVPTR (PL_curcop);
      PL_curcop = &cop;

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

  sv = sv_2mortal (sv);

  if (!(dec.flags & F_ALLOW_NONREF) && !SvROK (sv))
    croak ("JSON object or array expected (but number, string, true, false or null found, use allow_nonref to allow this)");

  return 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 = 7; i--; )
          {
            decode_hexdigit ['a' + i] = 10 + i;
            decode_hexdigit ['A' + i] = 10 + i;
          }

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

PROTOTYPES: DISABLE

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
        allow_nonref = F_ALLOW_NONREF
        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)));

PROTOTYPES: ENABLE

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:	1.5
Committed:	Thu Mar 22 23:24:18 2007 UTC (17 years, 2 months ago) by root
Branch:	MAIN
CVS Tags:	rel-0_2
Changes since 1.4:	+111 -68 lines
Log Message:	* empty log message *
#	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
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	#define F_ALLOW_NONREF 0x00000080
17
18	#define F_PRETTY F_INDENT \| F_SPACE_BEFORE \| F_SPACE_AFTER
19	#define F_DEFAULT 0
20
21	#define INIT_SIZE 32 // initial scalar size to be allocated
22
23	#define SB do {
24	#define SE } while (0)
25
26	static HV *json_stash;
27
28	// structure used for encoding JSON
29	typedef struct
30	{
31	char *cur;
32	STRLEN len; // SvLEN (sv)
33	char *end; // SvEND (sv)
34	SV *sv;
35	UV flags;
36	int max_recurse;
37	int indent;
38	} enc_t;
39
40	// structure used for decoding JSON
41	typedef struct
42	{
43	char *cur;
44	char *end;
45	const char *err;
46	UV flags;
47	} dec_t;
48
49	static UV *
50	SvJSON (SV *sv)
51	{
52	if (!(SvROK (sv) && SvOBJECT (SvRV (sv)) && SvSTASH (SvRV (sv)) == json_stash))
53	croak ("object is not of type JSON::XS");
54
55	return &SvUVX (SvRV (sv));
56	}
57
58	/////////////////////////////////////////////////////////////////////////////
59
60	static void
61	need (enc_t *enc, STRLEN len)
62	{
63	if (enc->cur + len >= enc->end)
64	{
65	STRLEN cur = enc->cur - SvPVX (enc->sv);
66	SvGROW (enc->sv, cur + len + 1);
67	enc->cur = SvPVX (enc->sv) + cur;
68	enc->end = SvPVX (enc->sv) + SvLEN (enc->sv);
69	}
70	}
71
72	static void
73	encode_ch (enc_t *enc, char ch)
74	{
75	need (enc, 1);
76	*enc->cur++ = ch;
77	}
78
79	static void
80	encode_str (enc_t enc, char str, STRLEN len, int is_utf8)
81	{
82	char *end = str + len;
83
84	need (enc, len);
85
86	while (str < end)
87	{
88	unsigned char ch = (unsigned char )str;
89
90	if (ch == '"')
91	{
92	need (enc, len += 1);
93	*enc->cur++ = '\\';
94	*enc->cur++ = '"';
95	++str;
96	}
97	else if (ch == '\\')
98	{
99	need (enc, len += 1);
100	*enc->cur++ = '\\';
101	*enc->cur++ = '\\';
102	++str;
103	}
104	else if (ch >= 0x20 && ch < 0x80) // most common case
105	{
106	*enc->cur++ = ch;
107	++str;
108	}
109	else if (ch == '\015')
110	{
111	need (enc, len += 1);
112	*enc->cur++ = '\\';
113	*enc->cur++ = 'r';
114	++str;
115	}
116	else if (ch == '\012')
117	{
118	need (enc, len += 1);
119	*enc->cur++ = '\\';
120	*enc->cur++ = 'n';
121	++str;
122	}
123	else
124	{
125	STRLEN clen;
126	UV uch;
127
128	if (is_utf8)
129	{
130	uch = utf8n_to_uvuni (str, end - str, &clen, UTF8_CHECK_ONLY);
131	if (clen == (STRLEN)-1)
132	croak ("malformed UTF-8 character in string, cannot convert to JSON");
133	}
134	else
135	{
136	uch = ch;
137	clen = 1;
138	}
139
140	if (uch < 0x80 \|\| enc->flags & F_ASCII)
141	{
142	if (uch > 0xFFFFUL)
143	{
144	need (enc, len += 11);
145	sprintf (enc->cur, "\\u%04x\\u%04x",
146	(uch - 0x10000) / 0x400 + 0xD800,
147	(uch - 0x10000) % 0x400 + 0xDC00);
148	enc->cur += 12;
149	}
150	else
151	{
152	static char hexdigit [16] = "0123456789abcdef";
153	need (enc, len += 5);
154	*enc->cur++ = '\\';
155	*enc->cur++ = 'u';
156	*enc->cur++ = hexdigit [ uch >> 12 ];
157	*enc->cur++ = hexdigit [(uch >> 8) & 15];
158	*enc->cur++ = hexdigit [(uch >> 4) & 15];
159	*enc->cur++ = hexdigit [(uch >> 0) & 15];
160	}
161
162	str += clen;
163	}
164	else if (is_utf8)
165	{
166	need (enc, len += clen);
167	do
168	{
169	enc->cur++ = str++;
170	}
171	while (--clen);
172	}
173	else
174	{
175	need (enc, 10); // never more than 11 bytes needed
176	enc->cur = uvuni_to_utf8_flags (enc->cur, uch, 0);
177	++str;
178	}
179	}
180
181	--len;
182	}
183	}
184
185	#define INDENT SB \
186	if (enc->flags & F_INDENT) \
187	{ \
188	int i_; \
189	need (enc, enc->indent); \
190	for (i_ = enc->indent * 3; i_--; )\
191	encode_ch (enc, ' '); \
192	} \
193	SE
194
195	#define SPACE SB need (enc, 1); encode_ch (enc, ' '); SE
196	#define NL SB if (enc->flags & F_INDENT) { need (enc, 1); encode_ch (enc, '\n'); } SE
197	#define COMMA SB \
198	encode_ch (enc, ','); \
199	if (enc->flags & F_INDENT) \
200	NL; \
201	else if (enc->flags & F_SPACE_AFTER) \
202	SPACE; \
203	SE
204
205	static void encode_sv (enc_t enc, SV sv);
206
207	static void
208	encode_av (enc_t enc, AV av)
209	{
210	int i, len = av_len (av);
211
212	encode_ch (enc, '['); NL;
213	++enc->indent;
214
215	for (i = 0; i <= len; ++i)
216	{
217	INDENT;
218	encode_sv (enc, *av_fetch (av, i, 0));
219
220	if (i < len)
221	COMMA;
222	}
223
224	NL;
225
226	--enc->indent;
227	INDENT; encode_ch (enc, ']');
228	}
229
230	static void
231	encode_he (enc_t enc, HE he)
232	{
233	encode_ch (enc, '"');
234
235	if (HeKLEN (he) == HEf_SVKEY)
236	{
237	SV *sv = HeSVKEY (he);
238	STRLEN len;
239	char *str;
240
241	SvGETMAGIC (sv);
242	str = SvPV (sv, len);
243
244	encode_str (enc, str, len, SvUTF8 (sv));
245	}
246	else
247	encode_str (enc, HeKEY (he), HeKLEN (he), HeKUTF8 (he));
248
249	encode_ch (enc, '"');
250
251	if (enc->flags & F_SPACE_BEFORE) SPACE;
252	encode_ch (enc, ':');
253	if (enc->flags & F_SPACE_AFTER ) SPACE;
254	encode_sv (enc, HeVAL (he));
255	}
256
257	// compare hash entries, used when all keys are bytestrings
258	static int
259	he_cmp_fast (const void a_, const void b_)
260	{
261	int cmp;
262
263	HE a = (HE **)a_;
264	HE b = (HE **)b_;
265
266	STRLEN la = HeKLEN (a);
267	STRLEN lb = HeKLEN (b);
268
269	if (!(cmp == memcmp (HeKEY (a), HeKEY (b), la < lb ? la : lb)))
270	cmp = la < lb ? -1 : la == lb ? 0 : 1;
271
272	return cmp;
273	}
274
275	// compare hash entries, used when some keys are sv's or utf-x
276	static int
277	he_cmp_slow (const void a, const void b)
278	{
279	return sv_cmp (HeSVKEY_force ((HE )a), HeSVKEY_force ((HE **)b));
280	}
281
282	static void
283	encode_hv (enc_t enc, HV hv)
284	{
285	int count, i;
286
287	encode_ch (enc, '{'); NL; ++enc->indent;
288
289	if ((count = hv_iterinit (hv)))
290	{
291	// for canonical output we have to sort by keys first
292	// actually, this is mostly due to the stupid so-called
293	// security workaround added somewhere in 5.8.x.
294	// that randomises hash orderings
295	if (enc->flags & F_CANONICAL)
296	{
297	HE he, hes [count];
298	int fast = 1;
299
300	i = 0;
301	while ((he = hv_iternext (hv)))
302	{
303	hes [i++] = he;
304	if (HeKLEN (he) < 0 \|\| HeKUTF8 (he))
305	fast = 0;
306	}
307
308	assert (i == count);
309
310	if (fast)
311	qsort (hes, count, sizeof (HE *), he_cmp_fast);
312	else
313	{
314	// hack to disable "use bytes"
315	COP *oldcop = PL_curcop, cop;
316	cop.op_private = 0;
317	PL_curcop = &cop;
318
319	SAVETMPS;
320	qsort (hes, count, sizeof (HE *), he_cmp_slow);
321	FREETMPS;
322
323	PL_curcop = oldcop;
324	}
325
326	for (i = 0; i < count; ++i)
327	{
328	INDENT;
329	encode_he (enc, hes [i]);
330
331	if (i < count - 1)
332	COMMA;
333	}
334
335	NL;
336	}
337	else
338	{
339	SV *sv;
340	HE *he = hv_iternext (hv);
341
342	for (;;)
343	{
344	INDENT;
345	encode_he (enc, he);
346
347	if (!(he = hv_iternext (hv)))
348	break;
349
350	COMMA;
351	}
352
353	NL;
354	}
355	}
356
357	--enc->indent; INDENT; encode_ch (enc, '}');
358	}
359
360	static void
361	encode_sv (enc_t enc, SV sv)
362	{
363	SvGETMAGIC (sv);
364
365	if (SvPOKp (sv))
366	{
367	STRLEN len;
368	char *str = SvPV (sv, len);
369	encode_ch (enc, '"');
370	encode_str (enc, str, len, SvUTF8 (sv));
371	encode_ch (enc, '"');
372	}
373	else if (SvNOKp (sv))
374	{
375	need (enc, NV_DIG + 32);
376	Gconvert (SvNVX (sv), NV_DIG, 0, enc->cur);
377	enc->cur += strlen (enc->cur);
378	}
379	else if (SvIOKp (sv))
380	{
381	need (enc, 64);
382	enc->cur +=
383	SvIsUV(sv)
384	? snprintf (enc->cur, 64, "%"UVuf, (UV)SvUVX (sv))
385	: snprintf (enc->cur, 64, "%"IVdf, (IV)SvIVX (sv));
386	}
387	else if (SvROK (sv))
388	{
389	if (!--enc->max_recurse)
390	croak ("data structure too deep (hit recursion limit)");
391
392	sv = SvRV (sv);
393
394	switch (SvTYPE (sv))
395	{
396	case SVt_PVAV: encode_av (enc, (AV *)sv); break;
397	case SVt_PVHV: encode_hv (enc, (HV *)sv); break;
398
399	default:
400	croak ("JSON can only represent references to arrays or hashes");
401	}
402	}
403	else if (!SvOK (sv))
404	encode_str (enc, "null", 4, 0);
405	else
406	croak ("encountered perl type that JSON cannot handle");
407	}
408
409	static SV *
410	encode_json (SV *scalar, UV flags)
411	{
412	if (!(flags & F_ALLOW_NONREF) && !SvROK (scalar))
413	croak ("hash- or arraref required (not a simple scalar, use allow_nonref to allow this)");
414
415	enc_t enc;
416	enc.flags = flags;
417	enc.sv = sv_2mortal (NEWSV (0, INIT_SIZE));
418	enc.cur = SvPVX (enc.sv);
419	enc.end = SvEND (enc.sv);
420	enc.max_recurse = 0;
421	enc.indent = 0;
422
423	SvPOK_only (enc.sv);
424	encode_sv (&enc, scalar);
425
426	if (!(flags & (F_ASCII \| F_UTF8)))
427	SvUTF8_on (enc.sv);
428
429	SvCUR_set (enc.sv, enc.cur - SvPVX (enc.sv));
430	return enc.sv;
431	}
432
433	/////////////////////////////////////////////////////////////////////////////
434
435	#define WS \
436	for (;;) \
437	{ \
438	char ch = *dec->cur; \
439	if (ch > 0x20 \
440	\|\| (ch != 0x20 && ch != 0x0a && ch != 0x0d && ch != 0x09)) \
441	break; \
442	++dec->cur; \
443	}
444
445	#define ERR(reason) SB dec->err = reason; goto fail; SE
446	#define EXPECT_CH(ch) SB \
447	if (*dec->cur != ch) \
448	ERR (# ch " expected"); \
449	++dec->cur; \
450	SE
451
452	static SV decode_sv (dec_t dec);
453
454	static signed char decode_hexdigit[256];
455
456	static UV
457	decode_4hex (dec_t *dec)
458	{
459	signed char d1, d2, d3, d4;
460
461	d1 = decode_hexdigit [((unsigned char *)dec->cur) [0]];
462	if (d1 < 0) ERR ("four hexadecimal digits expected");
463	d2 = decode_hexdigit [((unsigned char *)dec->cur) [1]];
464	if (d2 < 0) ERR ("four hexadecimal digits expected");
465	d3 = decode_hexdigit [((unsigned char *)dec->cur) [2]];
466	if (d3 < 0) ERR ("four hexadecimal digits expected");
467	d4 = decode_hexdigit [((unsigned char *)dec->cur) [3]];
468	if (d4 < 0) ERR ("four hexadecimal digits expected");
469
470	dec->cur += 4;
471
472	return ((UV)d1) << 12
473	\| ((UV)d2) << 8
474	\| ((UV)d3) << 4
475	\| ((UV)d4);
476
477	fail:
478	return (UV)-1;
479	}
480
481	#define APPEND_GROW(n) SB \
482	if (cur + (n) >= end) \
483	{ \
484	STRLEN ofs = cur - SvPVX (sv); \
485	SvGROW (sv, ofs + (n) + 1); \
486	cur = SvPVX (sv) + ofs; \
487	end = SvEND (sv); \
488	} \
489	SE
490
491	#define APPEND_CH(ch) SB \
492	APPEND_GROW (1); \
493	*cur++ = (ch); \
494	SE
495
496	static SV *
497	decode_str (dec_t *dec)
498	{
499	SV *sv = NEWSV (0,2);
500	int utf8 = 0;
501	char *cur = SvPVX (sv);
502	char *end = SvEND (sv);
503
504	for (;;)
505	{
506	unsigned char ch = (unsigned char )dec->cur;
507
508	if (ch == '"')
509	break;
510	else if (ch == '\\')
511	{
512	switch (*++dec->cur)
513	{
514	case '\\':
515	case '/':
516	case '"': APPEND_CH (*dec->cur++); break;
517
518	case 'b': APPEND_CH ('\010'); ++dec->cur; break;
519	case 't': APPEND_CH ('\011'); ++dec->cur; break;
520	case 'n': APPEND_CH ('\012'); ++dec->cur; break;
521	case 'f': APPEND_CH ('\014'); ++dec->cur; break;
522	case 'r': APPEND_CH ('\015'); ++dec->cur; break;
523
524	case 'u':
525	{
526	UV lo, hi;
527	++dec->cur;
528
529	hi = decode_4hex (dec);
530	if (hi == (UV)-1)
531	goto fail;
532
533	// possibly a surrogate pair
534	if (hi >= 0xd800 && hi < 0xdc00)
535	{
536	if (dec->cur [0] != '\\' \|\| dec->cur [1] != 'u')
537	ERR ("missing low surrogate character in surrogate pair");
538
539	dec->cur += 2;
540
541	lo = decode_4hex (dec);
542	if (lo == (UV)-1)
543	goto fail;
544
545	if (lo < 0xdc00 \|\| lo >= 0xe000)
546	ERR ("surrogate pair expected");
547
548	hi = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000;
549	}
550	else if (hi >= 0xdc00 && hi < 0xe000)
551	ERR ("missing high surrogate character in surrogate pair");
552
553	if (hi >= 0x80)
554	{
555	utf8 = 1;
556
557	APPEND_GROW (4); // at most 4 bytes for 21 bits
558	cur = (char *)uvuni_to_utf8_flags (cur, hi, 0);
559	}
560	else
561	APPEND_CH (hi);
562	}
563	break;
564
565	default:
566	--dec->cur;
567	ERR ("illegal backslash escape sequence in string");
568	}
569	}
570	else if (ch >= 0x20 && ch <= 0x7f)
571	APPEND_CH (*dec->cur++);
572	else if (ch >= 0x80)
573	{
574	STRLEN clen;
575	UV uch = utf8n_to_uvuni (dec->cur, dec->end - dec->cur, &clen, UTF8_CHECK_ONLY);
576	if (clen == (STRLEN)-1)
577	ERR ("malformed UTF-8 character in string, cannot convert to JSON");
578
579	APPEND_GROW (clen);
580	do
581	{
582	cur++ = dec->cur++;
583	}
584	while (--clen);
585
586	utf8 = 1;
587	}
588	else if (dec->cur == dec->end)
589	ERR ("unexpected end of string while parsing json string");
590	else
591	ERR ("invalid character encountered");
592	}
593
594	++dec->cur;
595
596	SvCUR_set (sv, cur - SvPVX (sv));
597
598	SvPOK_only (sv);
599	*SvEND (sv) = 0;
600
601	if (utf8)
602	SvUTF8_on (sv);
603
604	return sv;
605
606	fail:
607	SvREFCNT_dec (sv);
608	return 0;
609	}
610
611	static SV *
612	decode_num (dec_t *dec)
613	{
614	int is_nv = 0;
615	char *start = dec->cur;
616
617	// [minus]
618	if (*dec->cur == '-')
619	++dec->cur;
620
621	if (*dec->cur == '0')
622	{
623	++dec->cur;
624	if (dec->cur >= '0' && dec->cur <= '9')
625	ERR ("malformed number (leading zero must not be followed by another digit)");
626	}
627	else if (dec->cur < '0' \|\| dec->cur > '9')
628	ERR ("malformed number (no digits after initial minus)");
629	else
630	do
631	{
632	++dec->cur;
633	}
634	while (dec->cur >= '0' && dec->cur <= '9');
635
636	// [frac]
637	if (*dec->cur == '.')
638	{
639	++dec->cur;
640
641	if (dec->cur < '0' \|\| dec->cur > '9')
642	ERR ("malformed number (no digits after decimal point)");
643
644	do
645	{
646	++dec->cur;
647	}
648	while (dec->cur >= '0' && dec->cur <= '9');
649
650	is_nv = 1;
651	}
652
653	// [exp]
654	if (dec->cur == 'e' \|\| dec->cur == 'E')
655	{
656	++dec->cur;
657
658	if (dec->cur == '-' \|\| dec->cur == '+')
659	++dec->cur;
660
661	if (dec->cur < '0' \|\| dec->cur > '9')
662	ERR ("malformed number (no digits after exp sign)");
663
664	do
665	{
666	++dec->cur;
667	}
668	while (dec->cur >= '0' && dec->cur <= '9');
669
670	is_nv = 1;
671	}
672
673	if (!is_nv)
674	{
675	UV uv;
676	int numtype = grok_number (start, dec->cur - start, &uv);
677	if (numtype & IS_NUMBER_IN_UV)
678	if (numtype & IS_NUMBER_NEG)
679	{
680	if (uv < (UV)IV_MIN)
681	return newSViv (-(IV)uv);
682	}
683	else
684	return newSVuv (uv);
685	}
686
687	return newSVnv (Atof (start));
688
689	fail:
690	return 0;
691	}
692
693	static SV *
694	decode_av (dec_t *dec)
695	{
696	AV *av = newAV ();
697
698	WS;
699	if (*dec->cur == ']')
700	++dec->cur;
701	else
702	for (;;)
703	{
704	SV *value;
705
706	value = decode_sv (dec);
707	if (!value)
708	goto fail;
709
710	av_push (av, value);
711
712	WS;
713
714	if (*dec->cur == ']')
715	{
716	++dec->cur;
717	break;
718	}
719
720	if (*dec->cur != ',')
721	ERR (", or ] expected while parsing array");
722
723	++dec->cur;
724	}
725
726	return newRV_noinc ((SV *)av);
727
728	fail:
729	SvREFCNT_dec (av);
730	return 0;
731	}
732
733	static SV *
734	decode_hv (dec_t *dec)
735	{
736	HV *hv = newHV ();
737
738	WS;
739	if (*dec->cur == '}')
740	++dec->cur;
741	else
742	for (;;)
743	{
744	SV key, value;
745
746	WS; EXPECT_CH ('"');
747
748	key = decode_str (dec);
749	if (!key)
750	goto fail;
751
752	WS; EXPECT_CH (':');
753
754	value = decode_sv (dec);
755	if (!value)
756	{
757	SvREFCNT_dec (key);
758	goto fail;
759	}
760
761	//TODO: optimise
762	hv_store_ent (hv, key, value, 0);
763
764	WS;
765
766	if (*dec->cur == '}')
767	{
768	++dec->cur;
769	break;
770	}
771
772	if (*dec->cur != ',')
773	ERR (", or } expected while parsing object/hash");
774
775	++dec->cur;
776	}
777
778	return newRV_noinc ((SV *)hv);
779
780	fail:
781	SvREFCNT_dec (hv);
782	return 0;
783	}
784
785	static SV *
786	decode_sv (dec_t *dec)
787	{
788	WS;
789	switch (*dec->cur)
790	{
791	case '"': ++dec->cur; return decode_str (dec);
792	case '[': ++dec->cur; return decode_av (dec);
793	case '{': ++dec->cur; return decode_hv (dec);
794
795	case '-':
796	case '0': case '1': case '2': case '3': case '4':
797	case '5': case '6': case '7': case '8': case '9':
798	return decode_num (dec);
799
800	case 't':
801	if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "true", 4))
802	{
803	dec->cur += 4;
804	return newSViv (1);
805	}
806	else
807	ERR ("'true' expected");
808
809	break;
810
811	case 'f':
812	if (dec->end - dec->cur >= 5 && !memcmp (dec->cur, "false", 5))
813	{
814	dec->cur += 5;
815	return newSViv (0);
816	}
817	else
818	ERR ("'false' expected");
819
820	break;
821
822	case 'n':
823	if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "null", 4))
824	{
825	dec->cur += 4;
826	return newSVsv (&PL_sv_undef);
827	}
828	else
829	ERR ("'null' expected");
830
831	break;
832
833	default:
834	ERR ("malformed json string");
835	break;
836	}
837
838	fail:
839	return 0;
840	}
841
842	static SV *
843	decode_json (SV *string, UV flags)
844	{
845	SV *sv;
846
847	if (flags & F_UTF8)
848	sv_utf8_downgrade (string, 0);
849	else
850	sv_utf8_upgrade (string);
851
852	SvGROW (string, SvCUR (string) + 1); // should basically be a NOP
853
854	dec_t dec;
855	dec.flags = flags;
856	dec.cur = SvPVX (string);
857	dec.end = SvEND (string);
858	dec.err = 0;
859
860	sv = decode_sv (&dec);
861
862	if (!sv)
863	{
864	IV offset = utf8_distance (dec.cur, SvPVX (string));
865	SV *uni = sv_newmortal ();
866	// horrible hack to silence warning inside pv_uni_display
867	COP cop;
868	memset (&cop, 0, sizeof (cop));
869	cop.cop_warnings = pWARN_NONE;
870	SAVEVPTR (PL_curcop);
871	PL_curcop = &cop;
872
873	pv_uni_display (uni, dec.cur, dec.end - dec.cur, 20, UNI_DISPLAY_QQ);
874	croak ("%s, at character offset %d (%s)",
875	dec.err,
876	(int)offset,
877	dec.cur != dec.end ? SvPV_nolen (uni) : "(end of string)");
878	}
879
880	sv = sv_2mortal (sv);
881
882	if (!(dec.flags & F_ALLOW_NONREF) && !SvROK (sv))
883	croak ("JSON object or array expected (but number, string, true, false or null found, use allow_nonref to allow this)");
884
885	return sv;
886	}
887
888	MODULE = JSON::XS PACKAGE = JSON::XS
889
890	BOOT:
891	{
892	int i;
893
894	memset (decode_hexdigit, 0xff, 256);
895	for (i = 10; i--; )
896	decode_hexdigit ['0' + i] = i;
897
898	for (i = 7; i--; )
899	{
900	decode_hexdigit ['a' + i] = 10 + i;
901	decode_hexdigit ['A' + i] = 10 + i;
902	}
903
904	json_stash = gv_stashpv ("JSON::XS", 1);
905	}
906
907	PROTOTYPES: DISABLE
908
909	SV new (char dummy)
910	CODE:
911	RETVAL = sv_bless (newRV_noinc (newSVuv (F_DEFAULT)), json_stash);
912	OUTPUT:
913	RETVAL
914
915	SV ascii (SV self, int enable)
916	ALIAS:
917	ascii = F_ASCII
918	utf8 = F_UTF8
919	indent = F_INDENT
920	canonical = F_CANONICAL
921	space_before = F_SPACE_BEFORE
922	space_after = F_SPACE_AFTER
923	json_rpc = F_JSON_RPC
924	pretty = F_PRETTY
925	allow_nonref = F_ALLOW_NONREF
926	CODE:
927	{
928	UV *uv = SvJSON (self);
929	if (enable)
930	*uv \|= ix;
931	else
932	*uv &= ~ix;
933
934	RETVAL = newSVsv (self);
935	}
936	OUTPUT:
937	RETVAL
938
939	void encode (SV self, SV scalar)
940	PPCODE:
941	XPUSHs (encode_json (scalar, *SvJSON (self)));
942
943	void decode (SV self, SV jsonstr)
944	PPCODE:
945	XPUSHs (decode_json (jsonstr, *SvJSON (self)));
946
947	PROTOTYPES: ENABLE
948
949	void to_json (SV *scalar)
950	PPCODE:
951	XPUSHs (encode_json (scalar, F_UTF8));
952
953	void from_json (SV *jsonstr)
954	PPCODE:
955	XPUSHs (decode_json (jsonstr, F_UTF8));
956