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_SHRINK       0x00000100

#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 >= 0x20 && ch < 0x80) // most common case
        {
          if (ch == '"') // but with slow exceptions
            {
              need (enc, len += 1);
              *enc->cur++ = '\\';
              *enc->cur++ = '"';
            }
          else if (ch == '\\')
            {
              need (enc, len += 1);
              *enc->cur++ = '\\';
              *enc->cur++ = '\\';
            }
          else
            *enc->cur++ = ch;

          ++str;
        }
      else
        {
          switch (ch)
            {
              case '\010': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'b'; ++str; break;
              case '\011': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 't'; ++str; break;
              case '\012': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'n'; ++str; break;
              case '\014': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'f'; ++str; break;
              case '\015': need (enc, len += 1); *enc->cur++ = '\\'; *enc->cur++ = 'r'; ++str; break;

              default:
                {
                  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));

#ifdef SvPV_shrink_to_cur
  if (enc.flags & F_SHRINK)
    SvPV_shrink_to_cur (enc.sv);
#endif
  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);

#ifdef SvPV_shrink_to_cur
  if (dec->flags & F_SHRINK)
    SvPV_shrink_to_cur (sv);
#endif

  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 = 1)
        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
        shrink       = F_SHRINK
        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:	1.6
Committed:	Fri Mar 23 15:10:55 2007 UTC (17 years, 2 months ago) by root
Branch:	MAIN
Changes since 1.5:	+89 -79 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	#define F_SHRINK 0x00000100
18
19	#define F_PRETTY F_INDENT \| F_SPACE_BEFORE \| F_SPACE_AFTER
20	#define F_DEFAULT 0
21
22	#define INIT_SIZE 32 // initial scalar size to be allocated
23
24	#define SB do {
25	#define SE } while (0)
26
27	static HV *json_stash;
28
29	// structure used for encoding JSON
30	typedef struct
31	{
32	char *cur;
33	STRLEN len; // SvLEN (sv)
34	char *end; // SvEND (sv)
35	SV *sv;
36	UV flags;
37	int max_recurse;
38	int indent;
39	} enc_t;
40
41	// structure used for decoding JSON
42	typedef struct
43	{
44	char *cur;
45	char *end;
46	const char *err;
47	UV flags;
48	} dec_t;
49
50	static UV *
51	SvJSON (SV *sv)
52	{
53	if (!(SvROK (sv) && SvOBJECT (SvRV (sv)) && SvSTASH (SvRV (sv)) == json_stash))
54	croak ("object is not of type JSON::XS");
55
56	return &SvUVX (SvRV (sv));
57	}
58
59	/////////////////////////////////////////////////////////////////////////////
60
61	static void
62	need (enc_t *enc, STRLEN len)
63	{
64	if (enc->cur + len >= enc->end)
65	{
66	STRLEN cur = enc->cur - SvPVX (enc->sv);
67	SvGROW (enc->sv, cur + len + 1);
68	enc->cur = SvPVX (enc->sv) + cur;
69	enc->end = SvPVX (enc->sv) + SvLEN (enc->sv);
70	}
71	}
72
73	static void
74	encode_ch (enc_t *enc, char ch)
75	{
76	need (enc, 1);
77	*enc->cur++ = ch;
78	}
79
80	static void
81	encode_str (enc_t enc, char str, STRLEN len, int is_utf8)
82	{
83	char *end = str + len;
84
85	need (enc, len);
86
87	while (str < end)
88	{
89	unsigned char ch = (unsigned char )str;
90
91	if (ch >= 0x20 && ch < 0x80) // most common case
92	{
93	if (ch == '"') // but with slow exceptions
94	{
95	need (enc, len += 1);
96	*enc->cur++ = '\\';
97	*enc->cur++ = '"';
98	}
99	else if (ch == '\\')
100	{
101	need (enc, len += 1);
102	*enc->cur++ = '\\';
103	*enc->cur++ = '\\';
104	}
105	else
106	*enc->cur++ = ch;
107
108	++str;
109	}
110	else
111	{
112	switch (ch)
113	{
114	case '\010': need (enc, len += 1); enc->cur++ = '\\'; enc->cur++ = 'b'; ++str; break;
115	case '\011': need (enc, len += 1); enc->cur++ = '\\'; enc->cur++ = 't'; ++str; break;
116	case '\012': need (enc, len += 1); enc->cur++ = '\\'; enc->cur++ = 'n'; ++str; break;
117	case '\014': need (enc, len += 1); enc->cur++ = '\\'; enc->cur++ = 'f'; ++str; break;
118	case '\015': need (enc, len += 1); enc->cur++ = '\\'; enc->cur++ = 'r'; ++str; break;
119
120	default:
121	{
122	STRLEN clen;
123	UV uch;
124
125	if (is_utf8)
126	{
127	uch = utf8n_to_uvuni (str, end - str, &clen, UTF8_CHECK_ONLY);
128	if (clen == (STRLEN)-1)
129	croak ("malformed UTF-8 character in string, cannot convert to JSON");
130	}
131	else
132	{
133	uch = ch;
134	clen = 1;
135	}
136
137	if (uch < 0x80 \|\| enc->flags & F_ASCII)
138	{
139	if (uch > 0xFFFFUL)
140	{
141	need (enc, len += 11);
142	sprintf (enc->cur, "\\u%04x\\u%04x",
143	(uch - 0x10000) / 0x400 + 0xD800,
144	(uch - 0x10000) % 0x400 + 0xDC00);
145	enc->cur += 12;
146	}
147	else
148	{
149	static char hexdigit [16] = "0123456789abcdef";
150	need (enc, len += 5);
151	*enc->cur++ = '\\';
152	*enc->cur++ = 'u';
153	*enc->cur++ = hexdigit [ uch >> 12 ];
154	*enc->cur++ = hexdigit [(uch >> 8) & 15];
155	*enc->cur++ = hexdigit [(uch >> 4) & 15];
156	*enc->cur++ = hexdigit [(uch >> 0) & 15];
157	}
158
159	str += clen;
160	}
161	else if (is_utf8)
162	{
163	need (enc, len += clen);
164	do
165	{
166	enc->cur++ = str++;
167	}
168	while (--clen);
169	}
170	else
171	{
172	need (enc, 10); // never more than 11 bytes needed
173	enc->cur = uvuni_to_utf8_flags (enc->cur, uch, 0);
174	++str;
175	}
176	}
177	}
178	}
179
180	--len;
181	}
182	}
183
184	#define INDENT SB \
185	if (enc->flags & F_INDENT) \
186	{ \
187	int i_; \
188	need (enc, enc->indent); \
189	for (i_ = enc->indent * 3; i_--; )\
190	encode_ch (enc, ' '); \
191	} \
192	SE
193
194	#define SPACE SB need (enc, 1); encode_ch (enc, ' '); SE
195	#define NL SB if (enc->flags & F_INDENT) { need (enc, 1); encode_ch (enc, '\n'); } SE
196	#define COMMA SB \
197	encode_ch (enc, ','); \
198	if (enc->flags & F_INDENT) \
199	NL; \
200	else if (enc->flags & F_SPACE_AFTER) \
201	SPACE; \
202	SE
203
204	static void encode_sv (enc_t enc, SV sv);
205
206	static void
207	encode_av (enc_t enc, AV av)
208	{
209	int i, len = av_len (av);
210
211	encode_ch (enc, '['); NL;
212	++enc->indent;
213
214	for (i = 0; i <= len; ++i)
215	{
216	INDENT;
217	encode_sv (enc, *av_fetch (av, i, 0));
218
219	if (i < len)
220	COMMA;
221	}
222
223	NL;
224
225	--enc->indent;
226	INDENT; encode_ch (enc, ']');
227	}
228
229	static void
230	encode_he (enc_t enc, HE he)
231	{
232	encode_ch (enc, '"');
233
234	if (HeKLEN (he) == HEf_SVKEY)
235	{
236	SV *sv = HeSVKEY (he);
237	STRLEN len;
238	char *str;
239
240	SvGETMAGIC (sv);
241	str = SvPV (sv, len);
242
243	encode_str (enc, str, len, SvUTF8 (sv));
244	}
245	else
246	encode_str (enc, HeKEY (he), HeKLEN (he), HeKUTF8 (he));
247
248	encode_ch (enc, '"');
249
250	if (enc->flags & F_SPACE_BEFORE) SPACE;
251	encode_ch (enc, ':');
252	if (enc->flags & F_SPACE_AFTER ) SPACE;
253	encode_sv (enc, HeVAL (he));
254	}
255
256	// compare hash entries, used when all keys are bytestrings
257	static int
258	he_cmp_fast (const void a_, const void b_)
259	{
260	int cmp;
261
262	HE a = (HE **)a_;
263	HE b = (HE **)b_;
264
265	STRLEN la = HeKLEN (a);
266	STRLEN lb = HeKLEN (b);
267
268	if (!(cmp == memcmp (HeKEY (a), HeKEY (b), la < lb ? la : lb)))
269	cmp = la < lb ? -1 : la == lb ? 0 : 1;
270
271	return cmp;
272	}
273
274	// compare hash entries, used when some keys are sv's or utf-x
275	static int
276	he_cmp_slow (const void a, const void b)
277	{
278	return sv_cmp (HeSVKEY_force ((HE )a), HeSVKEY_force ((HE **)b));
279	}
280
281	static void
282	encode_hv (enc_t enc, HV hv)
283	{
284	int count, i;
285
286	encode_ch (enc, '{'); NL; ++enc->indent;
287
288	if ((count = hv_iterinit (hv)))
289	{
290	// for canonical output we have to sort by keys first
291	// actually, this is mostly due to the stupid so-called
292	// security workaround added somewhere in 5.8.x.
293	// that randomises hash orderings
294	if (enc->flags & F_CANONICAL)
295	{
296	HE he, hes [count];
297	int fast = 1;
298
299	i = 0;
300	while ((he = hv_iternext (hv)))
301	{
302	hes [i++] = he;
303	if (HeKLEN (he) < 0 \|\| HeKUTF8 (he))
304	fast = 0;
305	}
306
307	assert (i == count);
308
309	if (fast)
310	qsort (hes, count, sizeof (HE *), he_cmp_fast);
311	else
312	{
313	// hack to disable "use bytes"
314	COP *oldcop = PL_curcop, cop;
315	cop.op_private = 0;
316	PL_curcop = &cop;
317
318	SAVETMPS;
319	qsort (hes, count, sizeof (HE *), he_cmp_slow);
320	FREETMPS;
321
322	PL_curcop = oldcop;
323	}
324
325	for (i = 0; i < count; ++i)
326	{
327	INDENT;
328	encode_he (enc, hes [i]);
329
330	if (i < count - 1)
331	COMMA;
332	}
333
334	NL;
335	}
336	else
337	{
338	SV *sv;
339	HE *he = hv_iternext (hv);
340
341	for (;;)
342	{
343	INDENT;
344	encode_he (enc, he);
345
346	if (!(he = hv_iternext (hv)))
347	break;
348
349	COMMA;
350	}
351
352	NL;
353	}
354	}
355
356	--enc->indent; INDENT; encode_ch (enc, '}');
357	}
358
359	static void
360	encode_sv (enc_t enc, SV sv)
361	{
362	SvGETMAGIC (sv);
363
364	if (SvPOKp (sv))
365	{
366	STRLEN len;
367	char *str = SvPV (sv, len);
368	encode_ch (enc, '"');
369	encode_str (enc, str, len, SvUTF8 (sv));
370	encode_ch (enc, '"');
371	}
372	else if (SvNOKp (sv))
373	{
374	need (enc, NV_DIG + 32);
375	Gconvert (SvNVX (sv), NV_DIG, 0, enc->cur);
376	enc->cur += strlen (enc->cur);
377	}
378	else if (SvIOKp (sv))
379	{
380	need (enc, 64);
381	enc->cur +=
382	SvIsUV(sv)
383	? snprintf (enc->cur, 64, "%"UVuf, (UV)SvUVX (sv))
384	: snprintf (enc->cur, 64, "%"IVdf, (IV)SvIVX (sv));
385	}
386	else if (SvROK (sv))
387	{
388	if (!--enc->max_recurse)
389	croak ("data structure too deep (hit recursion limit)");
390
391	sv = SvRV (sv);
392
393	switch (SvTYPE (sv))
394	{
395	case SVt_PVAV: encode_av (enc, (AV *)sv); break;
396	case SVt_PVHV: encode_hv (enc, (HV *)sv); break;
397
398	default:
399	croak ("JSON can only represent references to arrays or hashes");
400	}
401	}
402	else if (!SvOK (sv))
403	encode_str (enc, "null", 4, 0);
404	else
405	croak ("encountered perl type that JSON cannot handle");
406	}
407
408	static SV *
409	encode_json (SV *scalar, UV flags)
410	{
411	if (!(flags & F_ALLOW_NONREF) && !SvROK (scalar))
412	croak ("hash- or arraref required (not a simple scalar, use allow_nonref to allow this)");
413
414	enc_t enc;
415	enc.flags = flags;
416	enc.sv = sv_2mortal (NEWSV (0, INIT_SIZE));
417	enc.cur = SvPVX (enc.sv);
418	enc.end = SvEND (enc.sv);
419	enc.max_recurse = 0;
420	enc.indent = 0;
421
422	SvPOK_only (enc.sv);
423	encode_sv (&enc, scalar);
424
425	if (!(flags & (F_ASCII \| F_UTF8)))
426	SvUTF8_on (enc.sv);
427
428	SvCUR_set (enc.sv, enc.cur - SvPVX (enc.sv));
429
430	#ifdef SvPV_shrink_to_cur
431	if (enc.flags & F_SHRINK)
432	SvPV_shrink_to_cur (enc.sv);
433	#endif
434	return enc.sv;
435	}
436
437	/////////////////////////////////////////////////////////////////////////////
438
439	#define WS \
440	for (;;) \
441	{ \
442	char ch = *dec->cur; \
443	if (ch > 0x20 \
444	\|\| (ch != 0x20 && ch != 0x0a && ch != 0x0d && ch != 0x09)) \
445	break; \
446	++dec->cur; \
447	}
448
449	#define ERR(reason) SB dec->err = reason; goto fail; SE
450	#define EXPECT_CH(ch) SB \
451	if (*dec->cur != ch) \
452	ERR (# ch " expected"); \
453	++dec->cur; \
454	SE
455
456	static SV decode_sv (dec_t dec);
457
458	static signed char decode_hexdigit[256];
459
460	static UV
461	decode_4hex (dec_t *dec)
462	{
463	signed char d1, d2, d3, d4;
464
465	d1 = decode_hexdigit [((unsigned char *)dec->cur) [0]];
466	if (d1 < 0) ERR ("four hexadecimal digits expected");
467	d2 = decode_hexdigit [((unsigned char *)dec->cur) [1]];
468	if (d2 < 0) ERR ("four hexadecimal digits expected");
469	d3 = decode_hexdigit [((unsigned char *)dec->cur) [2]];
470	if (d3 < 0) ERR ("four hexadecimal digits expected");
471	d4 = decode_hexdigit [((unsigned char *)dec->cur) [3]];
472	if (d4 < 0) ERR ("four hexadecimal digits expected");
473
474	dec->cur += 4;
475
476	return ((UV)d1) << 12
477	\| ((UV)d2) << 8
478	\| ((UV)d3) << 4
479	\| ((UV)d4);
480
481	fail:
482	return (UV)-1;
483	}
484
485	#define APPEND_GROW(n) SB \
486	if (cur + (n) >= end) \
487	{ \
488	STRLEN ofs = cur - SvPVX (sv); \
489	SvGROW (sv, ofs + (n) + 1); \
490	cur = SvPVX (sv) + ofs; \
491	end = SvEND (sv); \
492	} \
493	SE
494
495	#define APPEND_CH(ch) SB \
496	APPEND_GROW (1); \
497	*cur++ = (ch); \
498	SE
499
500	static SV *
501	decode_str (dec_t *dec)
502	{
503	SV *sv = NEWSV (0,2);
504	int utf8 = 0;
505	char *cur = SvPVX (sv);
506	char *end = SvEND (sv);
507
508	for (;;)
509	{
510	unsigned char ch = (unsigned char )dec->cur;
511
512	if (ch == '"')
513	break;
514	else if (ch == '\\')
515	{
516	switch (*++dec->cur)
517	{
518	case '\\':
519	case '/':
520	case '"': APPEND_CH (*dec->cur++); break;
521
522	case 'b': APPEND_CH ('\010'); ++dec->cur; break;
523	case 't': APPEND_CH ('\011'); ++dec->cur; break;
524	case 'n': APPEND_CH ('\012'); ++dec->cur; break;
525	case 'f': APPEND_CH ('\014'); ++dec->cur; break;
526	case 'r': APPEND_CH ('\015'); ++dec->cur; break;
527
528	case 'u':
529	{
530	UV lo, hi;
531	++dec->cur;
532
533	hi = decode_4hex (dec);
534	if (hi == (UV)-1)
535	goto fail;
536
537	// possibly a surrogate pair
538	if (hi >= 0xd800 && hi < 0xdc00)
539	{
540	if (dec->cur [0] != '\\' \|\| dec->cur [1] != 'u')
541	ERR ("missing low surrogate character in surrogate pair");
542
543	dec->cur += 2;
544
545	lo = decode_4hex (dec);
546	if (lo == (UV)-1)
547	goto fail;
548
549	if (lo < 0xdc00 \|\| lo >= 0xe000)
550	ERR ("surrogate pair expected");
551
552	hi = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000;
553	}
554	else if (hi >= 0xdc00 && hi < 0xe000)
555	ERR ("missing high surrogate character in surrogate pair");
556
557	if (hi >= 0x80)
558	{
559	utf8 = 1;
560
561	APPEND_GROW (4); // at most 4 bytes for 21 bits
562	cur = (char *)uvuni_to_utf8_flags (cur, hi, 0);
563	}
564	else
565	APPEND_CH (hi);
566	}
567	break;
568
569	default:
570	--dec->cur;
571	ERR ("illegal backslash escape sequence in string");
572	}
573	}
574	else if (ch >= 0x20 && ch <= 0x7f)
575	APPEND_CH (*dec->cur++);
576	else if (ch >= 0x80)
577	{
578	STRLEN clen;
579	UV uch = utf8n_to_uvuni (dec->cur, dec->end - dec->cur, &clen, UTF8_CHECK_ONLY);
580	if (clen == (STRLEN)-1)
581	ERR ("malformed UTF-8 character in string, cannot convert to JSON");
582
583	APPEND_GROW (clen);
584	do
585	{
586	cur++ = dec->cur++;
587	}
588	while (--clen);
589
590	utf8 = 1;
591	}
592	else if (dec->cur == dec->end)
593	ERR ("unexpected end of string while parsing json string");
594	else
595	ERR ("invalid character encountered");
596	}
597
598	++dec->cur;
599
600	SvCUR_set (sv, cur - SvPVX (sv));
601
602	SvPOK_only (sv);
603	*SvEND (sv) = 0;
604
605	if (utf8)
606	SvUTF8_on (sv);
607
608	#ifdef SvPV_shrink_to_cur
609	if (dec->flags & F_SHRINK)
610	SvPV_shrink_to_cur (sv);
611	#endif
612
613	return sv;
614
615	fail:
616	SvREFCNT_dec (sv);
617	return 0;
618	}
619
620	static SV *
621	decode_num (dec_t *dec)
622	{
623	int is_nv = 0;
624	char *start = dec->cur;
625
626	// [minus]
627	if (*dec->cur == '-')
628	++dec->cur;
629
630	if (*dec->cur == '0')
631	{
632	++dec->cur;
633	if (dec->cur >= '0' && dec->cur <= '9')
634	ERR ("malformed number (leading zero must not be followed by another digit)");
635	}
636	else if (dec->cur < '0' \|\| dec->cur > '9')
637	ERR ("malformed number (no digits after initial minus)");
638	else
639	do
640	{
641	++dec->cur;
642	}
643	while (dec->cur >= '0' && dec->cur <= '9');
644
645	// [frac]
646	if (*dec->cur == '.')
647	{
648	++dec->cur;
649
650	if (dec->cur < '0' \|\| dec->cur > '9')
651	ERR ("malformed number (no digits after decimal point)");
652
653	do
654	{
655	++dec->cur;
656	}
657	while (dec->cur >= '0' && dec->cur <= '9');
658
659	is_nv = 1;
660	}
661
662	// [exp]
663	if (dec->cur == 'e' \|\| dec->cur == 'E')
664	{
665	++dec->cur;
666
667	if (dec->cur == '-' \|\| dec->cur == '+')
668	++dec->cur;
669
670	if (dec->cur < '0' \|\| dec->cur > '9')
671	ERR ("malformed number (no digits after exp sign)");
672
673	do
674	{
675	++dec->cur;
676	}
677	while (dec->cur >= '0' && dec->cur <= '9');
678
679	is_nv = 1;
680	}
681
682	if (!is_nv)
683	{
684	UV uv;
685	int numtype = grok_number (start, dec->cur - start, &uv);
686	if (numtype & IS_NUMBER_IN_UV)
687	if (numtype & IS_NUMBER_NEG)
688	{
689	if (uv < (UV)IV_MIN)
690	return newSViv (-(IV)uv);
691	}
692	else
693	return newSVuv (uv);
694	}
695
696	return newSVnv (Atof (start));
697
698	fail:
699	return 0;
700	}
701
702	static SV *
703	decode_av (dec_t *dec)
704	{
705	AV *av = newAV ();
706
707	WS;
708	if (*dec->cur == ']')
709	++dec->cur;
710	else
711	for (;;)
712	{
713	SV *value;
714
715	value = decode_sv (dec);
716	if (!value)
717	goto fail;
718
719	av_push (av, value);
720
721	WS;
722
723	if (*dec->cur == ']')
724	{
725	++dec->cur;
726	break;
727	}
728
729	if (*dec->cur != ',')
730	ERR (", or ] expected while parsing array");
731
732	++dec->cur;
733	}
734
735	return newRV_noinc ((SV *)av);
736
737	fail:
738	SvREFCNT_dec (av);
739	return 0;
740	}
741
742	static SV *
743	decode_hv (dec_t *dec)
744	{
745	HV *hv = newHV ();
746
747	WS;
748	if (*dec->cur == '}')
749	++dec->cur;
750	else
751	for (;;)
752	{
753	SV key, value;
754
755	WS; EXPECT_CH ('"');
756
757	key = decode_str (dec);
758	if (!key)
759	goto fail;
760
761	WS; EXPECT_CH (':');
762
763	value = decode_sv (dec);
764	if (!value)
765	{
766	SvREFCNT_dec (key);
767	goto fail;
768	}
769
770	//TODO: optimise
771	hv_store_ent (hv, key, value, 0);
772
773	WS;
774
775	if (*dec->cur == '}')
776	{
777	++dec->cur;
778	break;
779	}
780
781	if (*dec->cur != ',')
782	ERR (", or } expected while parsing object/hash");
783
784	++dec->cur;
785	}
786
787	return newRV_noinc ((SV *)hv);
788
789	fail:
790	SvREFCNT_dec (hv);
791	return 0;
792	}
793
794	static SV *
795	decode_sv (dec_t *dec)
796	{
797	WS;
798	switch (*dec->cur)
799	{
800	case '"': ++dec->cur; return decode_str (dec);
801	case '[': ++dec->cur; return decode_av (dec);
802	case '{': ++dec->cur; return decode_hv (dec);
803
804	case '-':
805	case '0': case '1': case '2': case '3': case '4':
806	case '5': case '6': case '7': case '8': case '9':
807	return decode_num (dec);
808
809	case 't':
810	if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "true", 4))
811	{
812	dec->cur += 4;
813	return newSViv (1);
814	}
815	else
816	ERR ("'true' expected");
817
818	break;
819
820	case 'f':
821	if (dec->end - dec->cur >= 5 && !memcmp (dec->cur, "false", 5))
822	{
823	dec->cur += 5;
824	return newSViv (0);
825	}
826	else
827	ERR ("'false' expected");
828
829	break;
830
831	case 'n':
832	if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "null", 4))
833	{
834	dec->cur += 4;
835	return newSVsv (&PL_sv_undef);
836	}
837	else
838	ERR ("'null' expected");
839
840	break;
841
842	default:
843	ERR ("malformed json string");
844	break;
845	}
846
847	fail:
848	return 0;
849	}
850
851	static SV *
852	decode_json (SV *string, UV flags)
853	{
854	SV *sv;
855
856	if (flags & F_UTF8)
857	sv_utf8_downgrade (string, 0);
858	else
859	sv_utf8_upgrade (string);
860
861	SvGROW (string, SvCUR (string) + 1); // should basically be a NOP
862
863	dec_t dec;
864	dec.flags = flags;
865	dec.cur = SvPVX (string);
866	dec.end = SvEND (string);
867	dec.err = 0;
868
869	sv = decode_sv (&dec);
870
871	if (!sv)
872	{
873	IV offset = utf8_distance (dec.cur, SvPVX (string));
874	SV *uni = sv_newmortal ();
875	// horrible hack to silence warning inside pv_uni_display
876	COP cop;
877	memset (&cop, 0, sizeof (cop));
878	cop.cop_warnings = pWARN_NONE;
879	SAVEVPTR (PL_curcop);
880	PL_curcop = &cop;
881
882	pv_uni_display (uni, dec.cur, dec.end - dec.cur, 20, UNI_DISPLAY_QQ);
883	croak ("%s, at character offset %d (%s)",
884	dec.err,
885	(int)offset,
886	dec.cur != dec.end ? SvPV_nolen (uni) : "(end of string)");
887	}
888
889	sv = sv_2mortal (sv);
890
891	if (!(dec.flags & F_ALLOW_NONREF) && !SvROK (sv))
892	croak ("JSON object or array expected (but number, string, true, false or null found, use allow_nonref to allow this)");
893
894	return sv;
895	}
896
897	MODULE = JSON::XS PACKAGE = JSON::XS
898
899	BOOT:
900	{
901	int i;
902
903	memset (decode_hexdigit, 0xff, 256);
904	for (i = 10; i--; )
905	decode_hexdigit ['0' + i] = i;
906
907	for (i = 7; i--; )
908	{
909	decode_hexdigit ['a' + i] = 10 + i;
910	decode_hexdigit ['A' + i] = 10 + i;
911	}
912
913	json_stash = gv_stashpv ("JSON::XS", 1);
914	}
915
916	PROTOTYPES: DISABLE
917
918	SV new (char dummy)
919	CODE:
920	RETVAL = sv_bless (newRV_noinc (newSVuv (F_DEFAULT)), json_stash);
921	OUTPUT:
922	RETVAL
923
924	SV ascii (SV self, int enable = 1)
925	ALIAS:
926	ascii = F_ASCII
927	utf8 = F_UTF8
928	indent = F_INDENT
929	canonical = F_CANONICAL
930	space_before = F_SPACE_BEFORE
931	space_after = F_SPACE_AFTER
932	json_rpc = F_JSON_RPC
933	pretty = F_PRETTY
934	allow_nonref = F_ALLOW_NONREF
935	shrink = F_SHRINK
936	CODE:
937	{
938	UV *uv = SvJSON (self);
939	if (enable)
940	*uv \|= ix;
941	else
942	*uv &= ~ix;
943
944	RETVAL = newSVsv (self);
945	}
946	OUTPUT:
947	RETVAL
948
949	void encode (SV self, SV scalar)
950	PPCODE:
951	XPUSHs (encode_json (scalar, *SvJSON (self)));
952
953	void decode (SV self, SV jsonstr)
954	PPCODE:
955	XPUSHs (decode_json (jsonstr, *SvJSON (self)));
956
957	PROTOTYPES: ENABLE
958
959	void to_json (SV *scalar)
960	PPCODE:
961	XPUSHs (encode_json (scalar, F_UTF8));
962
963	void from_json (SV *jsonstr)
964	PPCODE:
965	XPUSHs (decode_json (jsonstr, F_UTF8));
966