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;
  char *err;
  UV flags;
} dec_t;

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

  return &SvUVX (SvRV (sv));
}

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

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

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

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

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

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

          need (enc, len += 6);

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

          str += clen;
        }

      --len;
    }
}

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

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

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

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

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

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

      if (i < len)
        COMMA;
    }

  NL;

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

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

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

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

  encode_ch (enc, '"');

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

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

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

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

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

  return cmp;
}

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

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

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

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

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

          assert (i == count);

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

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

              PL_curcop = oldcop;
            }

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

              if (i < count - 1)
                COMMA;
            }

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

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

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

              COMMA;
            }

          NL;
        }
    }

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

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

      sv = SvRV (sv);

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

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

static SV *
encode_json (SV *scalar, UV flags)
{
  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);

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

static signed char decode_hexdigit[256];

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

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

  dec->cur += 4;

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

fail:
  return (UV)-1;
}

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

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

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

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

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

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

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

                      dec->cur += 2;

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

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

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

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

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

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

  ++dec->cur;

  SvPOK_only (sv);

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

  if (utf8)
    SvUTF8_on (sv);

  return sv;

fail:
  SvREFCNT_dec (sv);
  return 0;
}

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

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

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

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

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

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

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

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

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

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

  return newSVnv (Atof (start));

fail:
  return 0;
}

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

  for (;;)
    {
      SV *value;

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

      av_push (av, value);

      WS;

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

      ++dec->cur;
    }

  return newRV_noinc ((SV *)av);

fail:
  SvREFCNT_dec (av);
  return 0;
}

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

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

      WS; EXPECT_CH ('"');

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

      WS; EXPECT_CH (':');

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

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

      WS;

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

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

      ++dec->cur;
    }

  return newRV_noinc ((SV *)hv);

fail:
  SvREFCNT_dec (hv);
  return 0;
}

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

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

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

        break;

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

        break;

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

        break;

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

fail:
  return 0;
}

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

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

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

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

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

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

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

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

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

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

SV *ascii (SV *self, int enable)
        ALIAS:
        ascii        = F_ASCII
        utf8         = F_UTF8
        indent       = F_INDENT
        canonical    = F_CANONICAL
        space_before = F_SPACE_BEFORE
        space_after  = F_SPACE_AFTER
        json_rpc     = F_JSON_RPC
        pretty       = F_PRETTY
        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)));

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:	1.3
Committed:	Thu Mar 22 18:10:29 2007 UTC (17 years, 2 months ago) by root
Branch:	MAIN
Changes since 1.2:	+11 -2 lines
Log Message:	rant
#	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			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 = SvEND (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			while (str < end)
85			{
86			unsigned char ch = (unsigned char )str;
87			if (ch >= 0x20 && ch < 0x80) // most common case
88			{
89			*enc->cur++ = ch;
90			str++;
91			}
92			else
93			{
94			STRLEN clen;
95			UV uch;
96
97			if (is_utf8)
98			{
99			uch = utf8n_to_uvuni (str, end - str, &clen, UTF8_CHECK_ONLY);
100			if (clen < 0)
101			croak ("malformed UTF-8 character in string, cannot convert to JSON");
102			}
103			else
104			{
105			uch = ch;
106			clen = 1;
107			}
108
109			need (enc, len += 6);
110
111			if (uch < 0xa0 \|\| enc->flags & F_ASCII)
112			{
113			if (uch > 0xFFFFUL)
114			{
115			len += 6;
116			need (enc, len += 6);
117			sprintf (enc->cur, "\\u%04x\\u%04x",
118			(uch - 0x10000) / 0x400 + 0xD800,
119			(uch - 0x10000) % 0x400 + 0xDC00);
120			enc->cur += 12;
121			}
122			else
123			{
124			sprintf (enc->cur, "\\u%04x", uch);
125			enc->cur += 6;
126			}
127			}
128			else if (is_utf8)
129			{
130			memcpy (enc->cur, str, clen);
131			enc->cur += clen;
132			}
133			else
134			enc->cur = uvuni_to_utf8_flags (enc->cur, uch, 0);
135
136			str += clen;
137			}
138
139			--len;
140			}
141			}
142
143			#define INDENT SB \
144			if (enc->flags & F_INDENT) \
145			{ \
146			int i_; \
147			need (enc, enc->indent); \
148			for (i_ = enc->indent * 3; i_--; )\
149			encode_ch (enc, ' '); \
150			} \
151			SE
152
153	root	1.2	#define SPACE SB need (enc, 1); encode_ch (enc, ' '); SE
154	root	1.1	#define NL SB if (enc->flags & F_INDENT) { need (enc, 1); encode_ch (enc, '\n'); } SE
155			#define COMMA SB \
156			encode_ch (enc, ','); \
157			if (enc->flags & F_INDENT) \
158			NL; \
159			else if (enc->flags & F_SPACE_AFTER) \
160			SPACE; \
161			SE
162
163			static void encode_sv (enc_t enc, SV sv);
164
165			static void
166			encode_av (enc_t enc, AV av)
167			{
168			int i, len = av_len (av);
169
170			encode_ch (enc, '['); NL;
171			++enc->indent;
172
173			for (i = 0; i <= len; ++i)
174			{
175			INDENT;
176			encode_sv (enc, *av_fetch (av, i, 0));
177
178			if (i < len)
179			COMMA;
180			}
181
182			NL;
183
184			--enc->indent;
185			INDENT; encode_ch (enc, ']');
186			}
187
188			static void
189			encode_he (enc_t enc, HE he)
190			{
191			encode_ch (enc, '"');
192
193			if (HeKLEN (he) == HEf_SVKEY)
194			{
195			SV *sv = HeSVKEY (he);
196			STRLEN len;
197			char *str = SvPV (sv, len);
198
199			encode_str (enc, str, len, SvUTF8 (sv));
200			}
201			else
202			encode_str (enc, HeKEY (he), HeKLEN (he), HeKUTF8 (he));
203
204			encode_ch (enc, '"');
205
206			if (enc->flags & F_SPACE_BEFORE) SPACE;
207			encode_ch (enc, ':');
208			if (enc->flags & F_SPACE_AFTER ) SPACE;
209			encode_sv (enc, HeVAL (he));
210			}
211
212			// compare hash entries, used when all keys are bytestrings
213			static int
214			he_cmp_fast (const void a_, const void b_)
215			{
216			int cmp;
217
218			HE a = (HE **)a_;
219			HE b = (HE **)b_;
220
221			STRLEN la = HeKLEN (a);
222			STRLEN lb = HeKLEN (b);
223
224			if (!(cmp == memcmp (HeKEY (a), HeKEY (b), la < lb ? la : lb)))
225			cmp = la < lb ? -1 : la == lb ? 0 : 1;
226
227			return cmp;
228			}
229
230			// compare hash entries, used when some keys are sv's or utf-x
231			static int
232			he_cmp_slow (const void a, const void b)
233			{
234			return sv_cmp (HeSVKEY_force ((HE )a), HeSVKEY_force ((HE **)b));
235			}
236
237			static void
238			encode_hv (enc_t enc, HV hv)
239			{
240			int count, i;
241
242			encode_ch (enc, '{'); NL; ++enc->indent;
243
244			if ((count = hv_iterinit (hv)))
245			{
246			// for canonical output we have to sort by keys first
247			// actually, this is mostly due to the stupid so-called
248			// security workaround added somewhere in 5.8.x.
249			// that randomises hash orderings
250			if (enc->flags & F_CANONICAL)
251			{
252			HE he, hes [count];
253			int fast = 1;
254
255			i = 0;
256			while ((he = hv_iternext (hv)))
257			{
258			hes [i++] = he;
259			if (HeKLEN (he) < 0 \|\| HeKUTF8 (he))
260			fast = 0;
261			}
262
263			assert (i == count);
264
265			if (fast)
266			qsort (hes, count, sizeof (HE *), he_cmp_fast);
267			else
268			{
269			// hack to disable "use bytes"
270			COP *oldcop = PL_curcop, cop;
271			cop.op_private = 0;
272			PL_curcop = &cop;
273
274			SAVETMPS;
275			qsort (hes, count, sizeof (HE *), he_cmp_slow);
276			FREETMPS;
277
278			PL_curcop = oldcop;
279			}
280
281			for (i = 0; i < count; ++i)
282			{
283			INDENT;
284			encode_he (enc, hes [i]);
285
286			if (i < count - 1)
287			COMMA;
288			}
289
290			NL;
291			}
292			else
293			{
294			SV *sv;
295			HE *he = hv_iternext (hv);
296
297			for (;;)
298			{
299			INDENT;
300			encode_he (enc, he);
301
302			if (!(he = hv_iternext (hv)))
303			break;
304
305			COMMA;
306			}
307
308			NL;
309			}
310			}
311
312			--enc->indent; INDENT; encode_ch (enc, '}');
313			}
314
315			static void
316			encode_sv (enc_t enc, SV sv)
317			{
318			if (SvPOKp (sv))
319			{
320			STRLEN len;
321			char *str = SvPV (sv, len);
322			encode_ch (enc, '"');
323			encode_str (enc, str, len, SvUTF8 (sv));
324			encode_ch (enc, '"');
325			}
326			else if (SvNOKp (sv))
327			{
328			need (enc, NV_DIG + 32);
329			Gconvert (SvNVX (sv), NV_DIG, 0, enc->cur);
330			enc->cur += strlen (enc->cur);
331			}
332			else if (SvIOKp (sv))
333			{
334			need (enc, 64);
335			enc->cur +=
336			SvIsUV(sv)
337			? snprintf (enc->cur, 64, "%"UVuf, (UV)SvUVX (sv))
338			: snprintf (enc->cur, 64, "%"IVdf, (IV)SvIVX (sv));
339			}
340			else if (SvROK (sv))
341			{
342			if (!--enc->max_recurse)
343			croak ("data structure too deep (hit recursion limit)");
344
345			sv = SvRV (sv);
346
347			switch (SvTYPE (sv))
348			{
349			case SVt_PVAV: encode_av (enc, (AV *)sv); break;
350			case SVt_PVHV: encode_hv (enc, (HV *)sv); break;
351
352			default:
353			croak ("JSON can only represent references to arrays or hashes");
354			}
355			}
356			else if (!SvOK (sv))
357			encode_str (enc, "null", 4, 0);
358			else
359			croak ("encountered perl type that JSON cannot handle");
360			}
361
362			static SV *
363			encode_json (SV *scalar, UV flags)
364			{
365	root	1.3	if (!(flags & F_ALLOW_NONREF) && !SvROK (scalar))
366			croak ("hash- or arraref required (not a simple scalar, use allow_nonref to allow this)");
367
368	root	1.1	enc_t enc;
369			enc.flags = flags;
370			enc.sv = sv_2mortal (NEWSV (0, INIT_SIZE));
371			enc.cur = SvPVX (enc.sv);
372			enc.end = SvEND (enc.sv);
373			enc.max_recurse = 0;
374			enc.indent = 0;
375
376			SvPOK_only (enc.sv);
377			encode_sv (&enc, scalar);
378
379			if (!(flags & (F_ASCII \| F_UTF8)))
380			SvUTF8_on (enc.sv);
381
382			SvCUR_set (enc.sv, enc.cur - SvPVX (enc.sv));
383			return enc.sv;
384			}
385
386			/////////////////////////////////////////////////////////////////////////////
387
388			#define WS \
389			for (;;) \
390			{ \
391			char ch = *dec->cur; \
392			if (ch > 0x20 \
393			\|\| (ch != 0x20 && ch != 0x0a && ch != 0x0d && ch != 0x09)) \
394			break; \
395			++dec->cur; \
396			}
397
398			#define ERR(reason) SB dec->err = reason; goto fail; SE
399			#define EXPECT_CH(ch) SB \
400			if (*dec->cur != ch) \
401			ERR (# ch " expected"); \
402			++dec->cur; \
403			SE
404
405			static SV decode_sv (dec_t dec);
406
407			#define APPEND_CH(ch) SB \
408			SvGROW (sv, cur + 1 + 1); \
409			SvPVX (sv)[cur++] = (ch); \
410			SE
411
412			static signed char decode_hexdigit[256];
413
414			static UV
415			decode_4hex (dec_t *dec)
416			{
417			signed char d1, d2, d3, d4;
418
419			d1 = decode_hexdigit [((unsigned char *)dec->cur) [0]];
420			if (d1 < 0) ERR ("four hexadecimal digits expected");
421			d2 = decode_hexdigit [((unsigned char *)dec->cur) [1]];
422			if (d2 < 0) ERR ("four hexadecimal digits expected");
423			d3 = decode_hexdigit [((unsigned char *)dec->cur) [2]];
424			if (d3 < 0) ERR ("four hexadecimal digits expected");
425			d4 = decode_hexdigit [((unsigned char *)dec->cur) [3]];
426			if (d4 < 0) ERR ("four hexadecimal digits expected");
427
428			dec->cur += 4;
429
430			return ((UV)d1) << 12
431			\| ((UV)d2) << 8
432			\| ((UV)d3) << 4
433			\| ((UV)d4);
434
435			fail:
436			return (UV)-1;
437			}
438
439			static SV *
440			decode_str (dec_t *dec)
441			{
442			SV *sv = NEWSV (0,2);
443			STRLEN cur = 0;
444			int utf8 = 0;
445
446			for (;;)
447			{
448			unsigned char ch = (unsigned char )dec->cur;
449
450			if (ch == '"')
451			break;
452			else if (ch == '\\')
453			{
454			switch (*++dec->cur)
455			{
456			case '\\':
457			case '/':
458			case '"': APPEND_CH (*dec->cur++); break;
459
460			case 'b': APPEND_CH ('\010'); ++dec->cur; break;
461			case 't': APPEND_CH ('\011'); ++dec->cur; break;
462			case 'n': APPEND_CH ('\012'); ++dec->cur; break;
463			case 'f': APPEND_CH ('\014'); ++dec->cur; break;
464			case 'r': APPEND_CH ('\015'); ++dec->cur; break;
465
466			case 'u':
467			{
468			UV lo, hi;
469			++dec->cur;
470
471			hi = decode_4hex (dec);
472			if (hi == (UV)-1)
473			goto fail;
474
475			// possibly a surrogate pair
476			if (hi >= 0xd800 && hi < 0xdc00)
477			{
478			if (dec->cur [0] != '\\' \|\| dec->cur [1] != 'u')
479			ERR ("illegal surrogate character");
480
481			dec->cur += 2;
482
483			lo = decode_4hex (dec);
484			if (lo == (UV)-1)
485			goto fail;
486
487			if (lo < 0xdc00 \|\| lo >= 0xe000)
488			ERR ("surrogate pair expected");
489
490			hi = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000;
491			}
492			else if (lo >= 0xdc00 && lo < 0xe000)
493			ERR ("illegal surrogate character");
494
495			if (hi >= 0x80)
496			{
497			utf8 = 1;
498
499			SvGROW (sv, cur + 4 + 1); // at most 4 bytes for 21 bits
500			cur = (char *)uvuni_to_utf8_flags (SvPVX (sv) + cur, hi, 0) - SvPVX (sv);
501			}
502			else
503			APPEND_CH (hi);
504			}
505			break;
506			}
507			}
508			else if (ch >= 0x20 && ch <= 0x7f)
509			APPEND_CH (*dec->cur++);
510			else if (ch >= 0x80)
511			{
512			STRLEN clen;
513			UV uch = utf8n_to_uvuni (dec->cur, dec->end - dec->cur, &clen, UTF8_CHECK_ONLY);
514			if (clen < 0)
515			ERR ("malformed UTF-8 character in string, cannot convert to JSON");
516
517			SvGROW (sv, cur + clen + 1); // at most 4 bytes for 21 bits
518			memcpy (SvPVX (sv) + cur, dec->cur, clen);
519			dec->cur += clen;
520			}
521			else
522			ERR ("invalid character encountered");
523			}
524
525			++dec->cur;
526
527			SvPOK_only (sv);
528
529			SvCUR_set (sv, cur);
530			*SvEND (sv) = 0;
531
532			if (utf8)
533			SvUTF8_on (sv);
534
535			return sv;
536
537			fail:
538			SvREFCNT_dec (sv);
539			return 0;
540			}
541
542			static SV *
543			decode_num (dec_t *dec)
544			{
545			int is_nv = 0;
546			char *start = dec->cur;
547
548			// [minus]
549			if (*dec->cur == '-')
550			++dec->cur;
551
552			if (*dec->cur == '0')
553			{
554			++dec->cur;
555			if (dec->cur >= '0' && dec->cur <= '9')
556			ERR ("malformed number (leading zero must not be followed by another digit)");
557			}
558
559			// int
560			while (dec->cur >= '0' && dec->cur <= '9')
561			++dec->cur;
562
563			// [frac]
564			if (*dec->cur == '.')
565			{
566			is_nv = 1;
567
568			do
569			{
570			++dec->cur;
571			}
572			while (dec->cur >= '0' && dec->cur <= '9');
573			}
574
575			// [exp]
576			if (dec->cur == 'e' \|\| dec->cur == 'E')
577			{
578			is_nv = 1;
579
580			++dec->cur;
581			if (dec->cur == '-' \|\| dec->cur == '+')
582			++dec->cur;
583
584			while (dec->cur >= '0' && dec->cur <= '9')
585			++dec->cur;
586			}
587
588			if (!is_nv)
589			{
590			UV uv;
591			int numtype = grok_number (start, dec->cur - start, &uv);
592			if (numtype & IS_NUMBER_IN_UV)
593			if (numtype & IS_NUMBER_NEG)
594			{
595			if (uv < (UV)IV_MIN)
596			return newSViv (-(IV)uv);
597			}
598			else
599			return newSVuv (uv);
600			}
601
602			return newSVnv (Atof (start));
603
604			fail:
605			return 0;
606			}
607
608			static SV *
609			decode_av (dec_t *dec)
610			{
611			AV *av = newAV ();
612
613			for (;;)
614			{
615			SV *value;
616
617			value = decode_sv (dec);
618			if (!value)
619			goto fail;
620
621			av_push (av, value);
622
623			WS;
624
625			if (*dec->cur == ']')
626			{
627			++dec->cur;
628			break;
629			}
630
631			if (*dec->cur != ',')
632			ERR (", or ] expected while parsing array");
633
634			++dec->cur;
635			}
636
637			return newRV_noinc ((SV *)av);
638
639			fail:
640			SvREFCNT_dec (av);
641			return 0;
642			}
643
644			static SV *
645			decode_hv (dec_t *dec)
646			{
647			HV *hv = newHV ();
648
649			for (;;)
650			{
651			SV key, value;
652
653			WS; EXPECT_CH ('"');
654
655			key = decode_str (dec);
656			if (!key)
657			goto fail;
658
659			WS; EXPECT_CH (':');
660
661			value = decode_sv (dec);
662			if (!value)
663			{
664			SvREFCNT_dec (key);
665			goto fail;
666			}
667
668			//TODO: optimise
669			hv_store_ent (hv, key, value, 0);
670
671			WS;
672
673			if (*dec->cur == '}')
674			{
675			++dec->cur;
676			break;
677			}
678
679			if (*dec->cur != ',')
680			ERR (", or } expected while parsing object/hash");
681
682			++dec->cur;
683			}
684
685			return newRV_noinc ((SV *)hv);
686
687			fail:
688			SvREFCNT_dec (hv);
689			return 0;
690			}
691
692			static SV *
693			decode_sv (dec_t *dec)
694			{
695			WS;
696			switch (*dec->cur)
697			{
698			case '"': ++dec->cur; return decode_str (dec);
699			case '[': ++dec->cur; return decode_av (dec);
700			case '{': ++dec->cur; return decode_hv (dec);
701
702			case '-':
703			case '0': case '1': case '2': case '3': case '4':
704			case '5': case '6': case '7': case '8': case '9':
705			return decode_num (dec);
706
707			case 't':
708			if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "true", 4))
709			{
710			dec->cur += 4;
711			return newSViv (1);
712			}
713			else
714			ERR ("'true' expected");
715
716			break;
717
718			case 'f':
719			if (dec->end - dec->cur >= 5 && !memcmp (dec->cur, "false", 5))
720			{
721			dec->cur += 5;
722			return newSViv (0);
723			}
724			else
725			ERR ("'false' expected");
726
727			break;
728
729			case 'n':
730			if (dec->end - dec->cur >= 4 && !memcmp (dec->cur, "null", 4))
731			{
732			dec->cur += 4;
733			return newSViv (1);
734			}
735			else
736			ERR ("'null' expected");
737
738			break;
739
740			default:
741			ERR ("malformed json string");
742			break;
743			}
744
745			fail:
746			return 0;
747			}
748
749			static SV *
750			decode_json (SV *string, UV flags)
751			{
752			SV *sv;
753
754			if (!(flags & F_UTF8))
755			sv_utf8_upgrade (string);
756
757			SvGROW (string, SvCUR (string) + 1); // should basically be a NOP
758
759			dec_t dec;
760			dec.flags = flags;
761			dec.cur = SvPVX (string);
762			dec.end = SvEND (string);
763			dec.err = 0;
764
765			*dec.end = 1; // invalid anywhere
766			sv = decode_sv (&dec);
767			*dec.end = 0;
768
769			if (!sv)
770			{
771			IV offset = utf8_distance (dec.cur, SvPVX (string));
772			SV *uni = sv_newmortal ();
773
774			pv_uni_display (uni, dec.cur, dec.end - dec.cur, 20, UNI_DISPLAY_QQ);
775			croak ("%s, at character %d (%s)",
776			dec.err,
777			(int)offset,
778			dec.cur != dec.end ? SvPV_nolen (uni) : "(end of string)");
779			}
780
781	root	1.3	sv = sv_2mortal (sv);
782
783			if (!(dec.flags & F_ALLOW_NONREF) && !SvROK (sv))
784			croak ("JSON object or array expected (but number, string, true, false or null found, use allow_nonref to allow this)");
785
786			return sv;
787	root	1.1	}
788
789			MODULE = JSON::XS PACKAGE = JSON::XS
790
791			BOOT:
792			{
793			int i;
794
795			memset (decode_hexdigit, 0xff, 256);
796			for (i = 10; i--; )
797			decode_hexdigit ['0' + i] = i;
798
799			for (i = 6; --i; )
800			{
801			decode_hexdigit ['a' + i] = 10 + i;
802			decode_hexdigit ['A' + i] = 10 + i;
803			}
804
805			json_stash = gv_stashpv ("JSON::XS", 1);
806			}
807
808			SV new (char dummy)
809			CODE:
810			RETVAL = sv_bless (newRV_noinc (newSVuv (F_DEFAULT)), json_stash);
811			OUTPUT:
812			RETVAL
813
814			SV ascii (SV self, int enable)
815			ALIAS:
816			ascii = F_ASCII
817			utf8 = F_UTF8
818			indent = F_INDENT
819			canonical = F_CANONICAL
820			space_before = F_SPACE_BEFORE
821			space_after = F_SPACE_AFTER
822			json_rpc = F_JSON_RPC
823	root	1.2	pretty = F_PRETTY
824	root	1.3	allow_nonref = F_ALLOW_NONREF
825	root	1.1	CODE:
826			{
827			UV *uv = SvJSON (self);
828			if (enable)
829			*uv \|= ix;
830			else
831			*uv &= ~ix;
832
833			RETVAL = newSVsv (self);
834			}
835			OUTPUT:
836			RETVAL
837
838			void encode (SV self, SV scalar)
839			PPCODE:
840			XPUSHs (encode_json (scalar, *SvJSON (self)));
841
842	root	1.2	void decode (SV self, SV jsonstr)
843	root	1.1	PPCODE:
844	root	1.2	XPUSHs (decode_json (jsonstr, *SvJSON (self)));
845
846			void to_json (SV *scalar)
847			PPCODE:
848			XPUSHs (encode_json (scalar, F_UTF8));
849
850			void from_json (SV *jsonstr)
851			PPCODE:
852			XPUSHs (decode_json (jsonstr, F_UTF8));
853	root	1.1