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 < 0)
                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);
              while (clen--)
                *enc->cur++ = *str++;
            }
          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 ("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;

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

          APPEND_GROW (clen);
          memcpy (cur, dec->cur, clen);
          cur += clen;
          dec->cur += clen;
        }
      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)");
    }

  // 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 = 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:	1.4
Committed:	Thu Mar 22 21:13:58 2007 UTC (17 years, 2 months ago) by root
Branch:	MAIN
CVS Tags:	rel-0_1
Changes since 1.3:	+90 -30 lines
Log Message:	* empty log message *
#	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	root	1.3	#define F_ALLOW_NONREF 0x00000080
17	root	1.1
18	root	1.2	#define F_PRETTY F_INDENT \| F_SPACE_BEFORE \| F_SPACE_AFTER
19	root	1.1	#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	root	1.4	const char *err;
46	root	1.1	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	root	1.4	enc->end = SvPVX (enc->sv) + SvLEN (enc->sv);
69	root	1.1	}
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	root	1.4	need (enc, len);
85
86	root	1.1	while (str < end)
87			{
88			unsigned char ch = (unsigned char )str;
89	root	1.4
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	root	1.1	{
106			*enc->cur++ = ch;
107	root	1.4	++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	root	1.1	}
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 < 0)
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	root	1.4	if (uch < 0x80 \|\| enc->flags & F_ASCII)
141	root	1.1	{
142			if (uch > 0xFFFFUL)
143			{
144	root	1.4	need (enc, len += 11);
145	root	1.1	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	root	1.4	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	root	1.1	}
161	root	1.4
162			str += clen;
163	root	1.1	}
164			else if (is_utf8)
165			{
166	root	1.4	need (enc, len += clen);
167			while (clen--)
168			enc->cur++ = str++;
169	root	1.1	}
170			else
171	root	1.4	{
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	root	1.1	}
177
178			--len;
179			}
180			}
181
182			#define INDENT SB \
183			if (enc->flags & F_INDENT) \
184			{ \
185			int i_; \
186			need (enc, enc->indent); \
187			for (i_ = enc->indent * 3; i_--; )\
188			encode_ch (enc, ' '); \
189			} \
190			SE
191
192	root	1.2	#define SPACE SB need (enc, 1); encode_ch (enc, ' '); SE
193	root	1.1	#define NL SB if (enc->flags & F_INDENT) { need (enc, 1); encode_ch (enc, '\n'); } SE
194			#define COMMA SB \
195			encode_ch (enc, ','); \
196			if (enc->flags & F_INDENT) \
197			NL; \
198			else if (enc->flags & F_SPACE_AFTER) \
199			SPACE; \
200			SE
201
202			static void encode_sv (enc_t enc, SV sv);
203
204			static void
205			encode_av (enc_t enc, AV av)
206			{
207			int i, len = av_len (av);
208
209			encode_ch (enc, '['); NL;
210			++enc->indent;
211
212			for (i = 0; i <= len; ++i)
213			{
214			INDENT;
215			encode_sv (enc, *av_fetch (av, i, 0));
216
217			if (i < len)
218			COMMA;
219			}
220
221			NL;
222
223			--enc->indent;
224			INDENT; encode_ch (enc, ']');
225			}
226
227			static void
228			encode_he (enc_t enc, HE he)
229			{
230			encode_ch (enc, '"');
231
232			if (HeKLEN (he) == HEf_SVKEY)
233			{
234			SV *sv = HeSVKEY (he);
235			STRLEN len;
236	root	1.4	char *str;
237
238			SvGETMAGIC (sv);
239			str = SvPV (sv, len);
240	root	1.1
241			encode_str (enc, str, len, SvUTF8 (sv));
242			}
243			else
244			encode_str (enc, HeKEY (he), HeKLEN (he), HeKUTF8 (he));
245
246			encode_ch (enc, '"');
247
248			if (enc->flags & F_SPACE_BEFORE) SPACE;
249			encode_ch (enc, ':');
250			if (enc->flags & F_SPACE_AFTER ) SPACE;
251			encode_sv (enc, HeVAL (he));
252			}
253
254			// compare hash entries, used when all keys are bytestrings
255			static int
256			he_cmp_fast (const void a_, const void b_)
257			{
258			int cmp;
259
260			HE a = (HE **)a_;
261			HE b = (HE **)b_;
262
263			STRLEN la = HeKLEN (a);
264			STRLEN lb = HeKLEN (b);
265
266			if (!(cmp == memcmp (HeKEY (a), HeKEY (b), la < lb ? la : lb)))
267			cmp = la < lb ? -1 : la == lb ? 0 : 1;
268
269			return cmp;
270			}
271
272			// compare hash entries, used when some keys are sv's or utf-x
273			static int
274			he_cmp_slow (const void a, const void b)
275			{
276			return sv_cmp (HeSVKEY_force ((HE )a), HeSVKEY_force ((HE **)b));
277			}
278
279			static void
280			encode_hv (enc_t enc, HV hv)
281			{
282			int count, i;
283
284			encode_ch (enc, '{'); NL; ++enc->indent;
285
286			if ((count = hv_iterinit (hv)))
287			{
288			// for canonical output we have to sort by keys first
289			// actually, this is mostly due to the stupid so-called
290			// security workaround added somewhere in 5.8.x.
291			// that randomises hash orderings
292			if (enc->flags & F_CANONICAL)
293			{
294			HE he, hes [count];
295			int fast = 1;
296
297			i = 0;
298			while ((he = hv_iternext (hv)))
299			{
300			hes [i++] = he;
301			if (HeKLEN (he) < 0 \|\| HeKUTF8 (he))
302			fast = 0;
303			}
304
305			assert (i == count);
306
307			if (fast)
308			qsort (hes, count, sizeof (HE *), he_cmp_fast);
309			else
310			{
311			// hack to disable "use bytes"
312			COP *oldcop = PL_curcop, cop;
313			cop.op_private = 0;
314			PL_curcop = &cop;
315
316			SAVETMPS;
317			qsort (hes, count, sizeof (HE *), he_cmp_slow);
318			FREETMPS;
319
320			PL_curcop = oldcop;
321			}
322
323			for (i = 0; i < count; ++i)
324			{
325			INDENT;
326			encode_he (enc, hes [i]);
327
328			if (i < count - 1)
329			COMMA;
330			}
331
332			NL;
333			}
334			else
335			{
336			SV *sv;
337			HE *he = hv_iternext (hv);
338
339			for (;;)
340			{
341			INDENT;
342			encode_he (enc, he);
343
344			if (!(he = hv_iternext (hv)))
345			break;
346
347			COMMA;
348			}
349
350			NL;
351			}
352			}
353
354			--enc->indent; INDENT; encode_ch (enc, '}');
355			}
356
357			static void
358			encode_sv (enc_t enc, SV sv)
359			{
360	root	1.4	SvGETMAGIC (sv);
361
362	root	1.1	if (SvPOKp (sv))
363			{
364			STRLEN len;
365			char *str = SvPV (sv, len);
366			encode_ch (enc, '"');
367			encode_str (enc, str, len, SvUTF8 (sv));
368			encode_ch (enc, '"');
369			}
370			else if (SvNOKp (sv))
371			{
372			need (enc, NV_DIG + 32);
373			Gconvert (SvNVX (sv), NV_DIG, 0, enc->cur);
374			enc->cur += strlen (enc->cur);
375			}
376			else if (SvIOKp (sv))
377			{
378			need (enc, 64);
379			enc->cur +=
380			SvIsUV(sv)
381			? snprintf (enc->cur, 64, "%"UVuf, (UV)SvUVX (sv))
382			: snprintf (enc->cur, 64, "%"IVdf, (IV)SvIVX (sv));
383			}
384			else if (SvROK (sv))
385			{
386			if (!--enc->max_recurse)
387			croak ("data structure too deep (hit recursion limit)");
388
389			sv = SvRV (sv);
390
391			switch (SvTYPE (sv))
392			{
393			case SVt_PVAV: encode_av (enc, (AV *)sv); break;
394			case SVt_PVHV: encode_hv (enc, (HV *)sv); break;
395
396			default:
397			croak ("JSON can only represent references to arrays or hashes");
398			}
399			}
400			else if (!SvOK (sv))
401			encode_str (enc, "null", 4, 0);
402			else
403			croak ("encountered perl type that JSON cannot handle");
404			}
405
406			static SV *
407			encode_json (SV *scalar, UV flags)
408			{
409	root	1.3	if (!(flags & F_ALLOW_NONREF) && !SvROK (scalar))
410			croak ("hash- or arraref required (not a simple scalar, use allow_nonref to allow this)");
411
412	root	1.1	enc_t enc;
413			enc.flags = flags;
414			enc.sv = sv_2mortal (NEWSV (0, INIT_SIZE));
415			enc.cur = SvPVX (enc.sv);
416			enc.end = SvEND (enc.sv);
417			enc.max_recurse = 0;
418			enc.indent = 0;
419
420			SvPOK_only (enc.sv);
421			encode_sv (&enc, scalar);
422
423			if (!(flags & (F_ASCII \| F_UTF8)))
424			SvUTF8_on (enc.sv);
425
426			SvCUR_set (enc.sv, enc.cur - SvPVX (enc.sv));
427			return enc.sv;
428			}
429
430			/////////////////////////////////////////////////////////////////////////////
431
432			#define WS \
433			for (;;) \
434			{ \
435			char ch = *dec->cur; \
436			if (ch > 0x20 \
437			\|\| (ch != 0x20 && ch != 0x0a && ch != 0x0d && ch != 0x09)) \
438			break; \
439			++dec->cur; \
440			}
441
442			#define ERR(reason) SB dec->err = reason; goto fail; SE
443			#define EXPECT_CH(ch) SB \
444			if (*dec->cur != ch) \
445			ERR (# ch " expected"); \
446			++dec->cur; \
447			SE
448
449			static SV decode_sv (dec_t dec);
450
451			static signed char decode_hexdigit[256];
452
453			static UV
454			decode_4hex (dec_t *dec)
455			{
456			signed char d1, d2, d3, d4;
457
458			d1 = decode_hexdigit [((unsigned char *)dec->cur) [0]];
459			if (d1 < 0) ERR ("four hexadecimal digits expected");
460			d2 = decode_hexdigit [((unsigned char *)dec->cur) [1]];
461			if (d2 < 0) ERR ("four hexadecimal digits expected");
462			d3 = decode_hexdigit [((unsigned char *)dec->cur) [2]];
463			if (d3 < 0) ERR ("four hexadecimal digits expected");
464			d4 = decode_hexdigit [((unsigned char *)dec->cur) [3]];
465			if (d4 < 0) ERR ("four hexadecimal digits expected");
466
467			dec->cur += 4;
468
469			return ((UV)d1) << 12
470			\| ((UV)d2) << 8
471			\| ((UV)d3) << 4
472			\| ((UV)d4);
473
474			fail:
475			return (UV)-1;
476			}
477
478	root	1.4	#define APPEND_GROW(n) SB \
479			if (cur + (n) >= end) \
480			{ \
481			STRLEN ofs = cur - SvPVX (sv); \
482			SvGROW (sv, ofs + (n) + 1); \
483			cur = SvPVX (sv) + ofs; \
484			end = SvEND (sv); \
485			} \
486			SE
487
488			#define APPEND_CH(ch) SB \
489			APPEND_GROW (1); \
490			*cur++ = (ch); \
491			SE
492
493	root	1.1	static SV *
494			decode_str (dec_t *dec)
495			{
496			SV *sv = NEWSV (0,2);
497			int utf8 = 0;
498	root	1.4	char *cur = SvPVX (sv);
499			char *end = SvEND (sv);
500	root	1.1
501			for (;;)
502			{
503			unsigned char ch = (unsigned char )dec->cur;
504
505			if (ch == '"')
506			break;
507			else if (ch == '\\')
508			{
509			switch (*++dec->cur)
510			{
511			case '\\':
512			case '/':
513			case '"': APPEND_CH (*dec->cur++); break;
514
515			case 'b': APPEND_CH ('\010'); ++dec->cur; break;
516			case 't': APPEND_CH ('\011'); ++dec->cur; break;
517			case 'n': APPEND_CH ('\012'); ++dec->cur; break;
518			case 'f': APPEND_CH ('\014'); ++dec->cur; break;
519			case 'r': APPEND_CH ('\015'); ++dec->cur; break;
520
521			case 'u':
522			{
523			UV lo, hi;
524			++dec->cur;
525
526			hi = decode_4hex (dec);
527			if (hi == (UV)-1)
528			goto fail;
529
530			// possibly a surrogate pair
531			if (hi >= 0xd800 && hi < 0xdc00)
532			{
533			if (dec->cur [0] != '\\' \|\| dec->cur [1] != 'u')
534			ERR ("illegal surrogate character");
535
536			dec->cur += 2;
537
538			lo = decode_4hex (dec);
539			if (lo == (UV)-1)
540			goto fail;
541
542			if (lo < 0xdc00 \|\| lo >= 0xe000)
543			ERR ("surrogate pair expected");
544
545			hi = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000;
546			}
547			else if (lo >= 0xdc00 && lo < 0xe000)
548			ERR ("illegal surrogate character");
549
550			if (hi >= 0x80)
551			{
552			utf8 = 1;
553
554	root	1.4	APPEND_GROW (4); // at most 4 bytes for 21 bits
555			cur = (char *)uvuni_to_utf8_flags (cur, hi, 0);
556	root	1.1	}
557			else
558			APPEND_CH (hi);
559			}
560			break;
561			}
562			}
563			else if (ch >= 0x20 && ch <= 0x7f)
564			APPEND_CH (*dec->cur++);
565			else if (ch >= 0x80)
566			{
567			STRLEN clen;
568			UV uch = utf8n_to_uvuni (dec->cur, dec->end - dec->cur, &clen, UTF8_CHECK_ONLY);
569			if (clen < 0)
570			ERR ("malformed UTF-8 character in string, cannot convert to JSON");
571
572	root	1.4	APPEND_GROW (clen);
573			memcpy (cur, dec->cur, clen);
574			cur += clen;
575	root	1.1	dec->cur += clen;
576			}
577			else
578			ERR ("invalid character encountered");
579			}
580
581			++dec->cur;
582
583	root	1.4	SvCUR_set (sv, cur - SvPVX (sv));
584
585	root	1.1	SvPOK_only (sv);
586			*SvEND (sv) = 0;
587
588			if (utf8)
589			SvUTF8_on (sv);
590
591			return sv;
592
593			fail:
594			SvREFCNT_dec (sv);
595			return 0;
596			}
597
598			static SV *
599			decode_num (dec_t *dec)
600			{
601			int is_nv = 0;
602			char *start = dec->cur;
603
604			// [minus]
605			if (*dec->cur == '-')
606			++dec->cur;
607
608			if (*dec->cur == '0')
609			{
610			++dec->cur;
611			if (dec->cur >= '0' && dec->cur <= '9')
612			ERR ("malformed number (leading zero must not be followed by another digit)");
613			}
614
615			// int
616			while (dec->cur >= '0' && dec->cur <= '9')
617			++dec->cur;
618
619			// [frac]
620			if (*dec->cur == '.')
621			{
622			is_nv = 1;
623
624			do
625			{
626			++dec->cur;
627			}
628			while (dec->cur >= '0' && dec->cur <= '9');
629			}
630
631			// [exp]
632			if (dec->cur == 'e' \|\| dec->cur == 'E')
633			{
634			is_nv = 1;
635
636			++dec->cur;
637			if (dec->cur == '-' \|\| dec->cur == '+')
638			++dec->cur;
639
640			while (dec->cur >= '0' && dec->cur <= '9')
641			++dec->cur;
642			}
643
644			if (!is_nv)
645			{
646			UV uv;
647			int numtype = grok_number (start, dec->cur - start, &uv);
648			if (numtype & IS_NUMBER_IN_UV)
649			if (numtype & IS_NUMBER_NEG)
650			{
651			if (uv < (UV)IV_MIN)
652			return newSViv (-(IV)uv);
653			}
654			else
655			return newSVuv (uv);
656			}
657
658			return newSVnv (Atof (start));
659
660			fail:
661			return 0;
662			}
663
664			static SV *
665			decode_av (dec_t *dec)
666			{
667			AV *av = newAV ();
668
669			for (;;)
670			{
671			SV *value;
672
673			value = decode_sv (dec);
674			if (!value)
675			goto fail;
676
677			av_push (av, value);
678
679			WS;
680
681			if (*dec->cur == ']')
682			{
683			++dec->cur;
684			break;
685			}
686
687			if (*dec->cur != ',')
688			ERR (", or ] expected while parsing array");
689
690			++dec->cur;
691			}
692
693			return newRV_noinc ((SV *)av);
694
695			fail:
696			SvREFCNT_dec (av);
697			return 0;
698			}
699
700			static SV *
701			decode_hv (dec_t *dec)
702			{
703			HV *hv = newHV ();
704
705			for (;;)
706			{
707			SV key, value;
708
709			WS; EXPECT_CH ('"');
710
711			key = decode_str (dec);
712			if (!key)
713			goto fail;
714
715			WS; EXPECT_CH (':');
716
717			value = decode_sv (dec);
718			if (!value)
719			{
720			SvREFCNT_dec (key);
721			goto fail;
722			}
723
724			//TODO: optimise
725			hv_store_ent (hv, key, value, 0);
726
727			WS;
728
729			if (*dec->cur == '}')
730			{
731			++dec->cur;
732			break;
733			}
734
735			if (*dec->cur != ',')
736			ERR (", or } expected while parsing object/hash");
737
738			++dec->cur;
739			}
740
741			return newRV_noinc ((SV *)hv);
742
743			fail:
744			SvREFCNT_dec (hv);
745			return 0;
746			}
747
748			static SV *
749			decode_sv (dec_t *dec)
750			{
751			WS;
752			switch (*dec->cur)
753			{
754			case '"': ++dec->cur; return decode_str (dec);
755			case '[': ++dec->cur; return decode_av (dec);
756			case '{': ++dec->cur; return decode_hv (dec);
757
758			case '-':
759			case '0': case '1': case '2': case '3': case '4':
760			case '5': case '6': case '7': case '8': case '9':
761			return decode_num (dec);
762
763			case 't':
764			if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "true", 4))
765			{
766			dec->cur += 4;
767			return newSViv (1);
768			}
769			else
770			ERR ("'true' expected");
771
772			break;
773
774			case 'f':
775			if (dec->end - dec->cur >= 5 && !memcmp (dec->cur, "false", 5))
776			{
777			dec->cur += 5;
778			return newSViv (0);
779			}
780			else
781			ERR ("'false' expected");
782
783			break;
784
785			case 'n':
786			if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "null", 4))
787			{
788			dec->cur += 4;
789			return newSViv (1);
790			}
791			else
792			ERR ("'null' expected");
793
794			break;
795
796			default:
797			ERR ("malformed json string");
798			break;
799			}
800
801			fail:
802			return 0;
803			}
804
805			static SV *
806			decode_json (SV *string, UV flags)
807			{
808			SV *sv;
809
810			if (!(flags & F_UTF8))
811			sv_utf8_upgrade (string);
812
813			SvGROW (string, SvCUR (string) + 1); // should basically be a NOP
814
815			dec_t dec;
816			dec.flags = flags;
817			dec.cur = SvPVX (string);
818			dec.end = SvEND (string);
819			dec.err = 0;
820
821			*dec.end = 1; // invalid anywhere
822			sv = decode_sv (&dec);
823			*dec.end = 0;
824
825			if (!sv)
826			{
827			IV offset = utf8_distance (dec.cur, SvPVX (string));
828			SV *uni = sv_newmortal ();
829
830			pv_uni_display (uni, dec.cur, dec.end - dec.cur, 20, UNI_DISPLAY_QQ);
831			croak ("%s, at character %d (%s)",
832			dec.err,
833			(int)offset,
834			dec.cur != dec.end ? SvPV_nolen (uni) : "(end of string)");
835			}
836
837	root	1.3	sv = sv_2mortal (sv);
838
839			if (!(dec.flags & F_ALLOW_NONREF) && !SvROK (sv))
840			croak ("JSON object or array expected (but number, string, true, false or null found, use allow_nonref to allow this)");
841
842			return sv;
843	root	1.1	}
844
845			MODULE = JSON::XS PACKAGE = JSON::XS
846
847			BOOT:
848			{
849			int i;
850
851			memset (decode_hexdigit, 0xff, 256);
852			for (i = 10; i--; )
853			decode_hexdigit ['0' + i] = i;
854
855	root	1.4	for (i = 7; i--; )
856	root	1.1	{
857			decode_hexdigit ['a' + i] = 10 + i;
858			decode_hexdigit ['A' + i] = 10 + i;
859			}
860
861			json_stash = gv_stashpv ("JSON::XS", 1);
862			}
863
864	root	1.4	PROTOTYPES: DISABLE
865
866	root	1.1	SV new (char dummy)
867			CODE:
868			RETVAL = sv_bless (newRV_noinc (newSVuv (F_DEFAULT)), json_stash);
869			OUTPUT:
870			RETVAL
871
872			SV ascii (SV self, int enable)
873			ALIAS:
874			ascii = F_ASCII
875			utf8 = F_UTF8
876			indent = F_INDENT
877			canonical = F_CANONICAL
878			space_before = F_SPACE_BEFORE
879			space_after = F_SPACE_AFTER
880			json_rpc = F_JSON_RPC
881	root	1.2	pretty = F_PRETTY
882	root	1.3	allow_nonref = F_ALLOW_NONREF
883	root	1.1	CODE:
884			{
885			UV *uv = SvJSON (self);
886			if (enable)
887			*uv \|= ix;
888			else
889			*uv &= ~ix;
890
891			RETVAL = newSVsv (self);
892			}
893			OUTPUT:
894			RETVAL
895
896			void encode (SV self, SV scalar)
897			PPCODE:
898			XPUSHs (encode_json (scalar, *SvJSON (self)));
899
900	root	1.2	void decode (SV self, SV jsonstr)
901	root	1.1	PPCODE:
902	root	1.2	XPUSHs (decode_json (jsonstr, *SvJSON (self)));
903
904	root	1.4	PROTOTYPES: ENABLE
905
906	root	1.2	void to_json (SV *scalar)
907			PPCODE:
908			XPUSHs (encode_json (scalar, F_UTF8));
909
910			void from_json (SV *jsonstr)
911			PPCODE:
912			XPUSHs (decode_json (jsonstr, F_UTF8));
913	root	1.1