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

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

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

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

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

      if (i < len)
        COMMA;
    }

  NL;

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

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

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

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

  encode_ch (enc, '"');

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

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

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

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

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

  return cmp;
}

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

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

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

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

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

          assert (i == count);

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

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

              PL_curcop = oldcop;
            }

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

              if (i < count - 1)
                COMMA;
            }

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

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

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

              COMMA;
            }

          NL;
        }
    }

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

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

      sv = SvRV (sv);

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

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

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

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

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

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

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

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

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

static SV *decode_sv (dec_t *dec);

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

static signed char decode_hexdigit[256];

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

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

  dec->cur += 4;

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

fail:
  return (UV)-1;
}

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

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

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

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

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

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

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

                      dec->cur += 2;

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

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

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

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

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

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

  ++dec->cur;

  SvPOK_only (sv);

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

  if (utf8)
    SvUTF8_on (sv);

  return sv;

fail:
  SvREFCNT_dec (sv);
  return 0;
}

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

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

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

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

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

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

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

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

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

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

  return newSVnv (Atof (start));

fail:
  return 0;
}

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

  for (;;)
    {
      SV *value;

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

      av_push (av, value);

      WS;

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

      ++dec->cur;
    }

  return newRV_noinc ((SV *)av);

fail:
  SvREFCNT_dec (av);
  return 0;
}

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

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

      WS; EXPECT_CH ('"');

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

      WS; EXPECT_CH (':');

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

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

      WS;

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

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

      ++dec->cur;
    }

  return newRV_noinc ((SV *)hv);

fail:
  SvREFCNT_dec (hv);
  return 0;
}

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

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

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

        break;

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

        break;

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

        break;

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

fail:
  return 0;
}

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

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

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

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

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

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

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

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

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

BOOT:
{
        int i;

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

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

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

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

SV *ascii (SV *self, int enable)
        ALIAS:
        ascii        = F_ASCII
        utf8         = F_UTF8
        indent       = F_INDENT
        canonical    = F_CANONICAL
        space_before = F_SPACE_BEFORE
        space_after  = F_SPACE_AFTER
        json_rpc     = F_JSON_RPC
        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 *jsondata)
        PPCODE:
        XPUSHs (decode_json (jsondata, *SvJSON (self)));

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