json_tokener.c

/*
 * $Id: json_tokener.c,v 1.20 2006/07/25 03:24:50 mclark Exp $
 *
 * Copyright (c) 2004, 2005 Metaparadigm Pte. Ltd.
 * Michael Clark <michael@metaparadigm.com>
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of the MIT license. See COPYING for details.
 *
 *
 * Copyright (c) 2008-2009 Yahoo! Inc.  All rights reserved.
 * The copyrights to the contents of this file are licensed under the MIT License
 * (http://www.opensource.org/licenses/mit-license.php)
 */

#include "config.h"

#include <math.h>
#include "math_compat.h"
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <ctype.h>
#include <string.h>
#include <limits.h>

#include "debug.h"
#include "printbuf.h"
#include "arraylist.h"
#include "json_inttypes.h"
#include "json_object.h"
#include "json_tokener.h"
#include "json_util.h"
#include "strdup_compat.h"

#ifdef HAVE_LOCALE_H
#include <locale.h>
#endif /* HAVE_LOCALE_H */
#ifdef HAVE_XLOCALE_H
#include <xlocale.h>
#endif

#define jt_hexdigit(x) (((x) <= '9') ? (x) - '0' : ((x) & 7) + 9)

#if !HAVE_STRNCASECMP && defined(_MSC_VER)
  /* MSC has the version as _strnicmp */
# define strncasecmp _strnicmp
#elif !HAVE_STRNCASECMP
# error You do not have strncasecmp on your system.
#endif /* HAVE_STRNCASECMP */

/* Use C99 NAN by default; if not available, nan("") should work too. */
#ifndef NAN
#define NAN nan("")
#endif /* !NAN */

static const char json_null_str[] = "null";
static const int json_null_str_len = sizeof(json_null_str) - 1;
static const char json_inf_str[] = "Infinity";
static const int json_inf_str_len = sizeof(json_inf_str) - 1;
static const char json_nan_str[] = "NaN";
static const int json_nan_str_len = sizeof(json_nan_str) - 1;
static const char json_true_str[] = "true";
static const int json_true_str_len = sizeof(json_true_str) - 1;
static const char json_false_str[] = "false";
static const int json_false_str_len = sizeof(json_false_str) - 1;

static const char* json_tokener_errors[] = {
  "success",
  "continue",
  "nesting too deep",
  "unexpected end of data",
  "unexpected character",
  "null expected",
  "boolean expected",
  "number expected",
  "array value separator ',' expected",
  "quoted object property name expected",
  "object property name separator ':' expected",
  "object value separator ',' expected",
  "invalid string sequence",
  "expected comment",
  "buffer size overflow"
};

const char *json_tokener_error_desc(enum json_tokener_error jerr)
{
	int jerr_int = (int) jerr;
	if (jerr_int < 0 ||
	    jerr_int >= (int)(sizeof(json_tokener_errors) / sizeof(json_tokener_errors[0])))
		return "Unknown error, "
		       "invalid json_tokener_error value passed to json_tokener_error_desc()";
	return json_tokener_errors[jerr];
}

enum json_tokener_error json_tokener_get_error(json_tokener *tok)
{
	return tok->err;
}

/* Stuff for decoding unicode sequences */
#define IS_HIGH_SURROGATE(uc) (((uc) & 0xFC00) == 0xD800)
#define IS_LOW_SURROGATE(uc)  (((uc) & 0xFC00) == 0xDC00)
#define DECODE_SURROGATE_PAIR(hi,lo) ((((hi) & 0x3FF) << 10) + ((lo) & 0x3FF) + 0x10000)
static unsigned char utf8_replacement_char[3] = { 0xEF, 0xBF, 0xBD };

struct json_tokener* json_tokener_new_ex(int depth)
{
  struct json_tokener *tok;

  tok = (struct json_tokener*)calloc(1, sizeof(struct json_tokener));
  if (!tok) return NULL;
  tok->stack = (struct json_tokener_srec *) calloc(depth,
						   sizeof(struct json_tokener_srec));
  if (!tok->stack) {
    free(tok);
    return NULL;
  }
  tok->pb = printbuf_new();
  tok->max_depth = depth;
  json_tokener_reset(tok);
  return tok;
}

struct json_tokener* json_tokener_new(void)
{
  return json_tokener_new_ex(JSON_TOKENER_DEFAULT_DEPTH);
}

void json_tokener_free(struct json_tokener *tok)
{
  json_tokener_reset(tok);
  if (tok->pb) printbuf_free(tok->pb);
  free(tok->stack);
  free(tok);
}

static void json_tokener_reset_level(struct json_tokener *tok, int depth)
{
  tok->stack[depth].state = json_tokener_state_eatws;
  tok->stack[depth].saved_state = json_tokener_state_start;
  json_object_put(tok->stack[depth].current);
  tok->stack[depth].current = NULL;
  free(tok->stack[depth].obj_field_name);
  tok->stack[depth].obj_field_name = NULL;
}

void json_tokener_reset(struct json_tokener *tok)
{
  int i;
  if (!tok)
    return;

  for(i = tok->depth; i >= 0; i--)
    json_tokener_reset_level(tok, i);
  tok->depth = 0;
  tok->err = json_tokener_success;
}

struct json_object* json_tokener_parse(const char *str)
{
    enum json_tokener_error jerr_ignored;
    struct json_object* obj;
    obj = json_tokener_parse_verbose(str, &jerr_ignored);
    return obj;
}

struct json_object* json_tokener_parse_verbose(const char *str,
					       enum json_tokener_error *error)
{
    struct json_tokener* tok;
    struct json_object* obj;

    tok = json_tokener_new();
    if (!tok)
      return NULL;
    obj = json_tokener_parse_ex(tok, str, -1);
    *error = tok->err;
    if(tok->err != json_tokener_success) {
		if (obj != NULL)
			json_object_put(obj);
        obj = NULL;
    }

    json_tokener_free(tok);
    return obj;
}

#define state  tok->stack[tok->depth].state
#define saved_state  tok->stack[tok->depth].saved_state
#define current tok->stack[tok->depth].current
#define obj_field_name tok->stack[tok->depth].obj_field_name

/* Optimization:
 * json_tokener_parse_ex() consumed a lot of CPU in its main loop,
 * iterating character-by character.  A large performance boost is
 * achieved by using tighter loops to locally handle units such as
 * comments and strings.  Loops that handle an entire token within
 * their scope also gather entire strings and pass them to
 * printbuf_memappend() in a single call, rather than calling
 * printbuf_memappend() one char at a time.
 *
 * PEEK_CHAR() and ADVANCE_CHAR() macros are used for code that is
 * common to both the main loop and the tighter loops.
 */

/* PEEK_CHAR(dest, tok) macro:
 *   Peeks at the current char and stores it in dest.
 *   Returns 1 on success, sets tok->err and returns 0 if no more chars.
 *   Implicit inputs:  str, len vars
 */
#define PEEK_CHAR(dest, tok)			\
  (((tok)->char_offset == len) ?		\
   (((tok)->depth == 0 &&			\
     state == json_tokener_state_eatws &&	\
     saved_state == json_tokener_state_finish	\
     ) ?					\
    (((tok)->err = json_tokener_success), 0)	\
    :						\
    (((tok)->err = json_tokener_continue), 0)	\
    ) :						\
   (((dest) = *str), 1)				\
   )

/* ADVANCE_CHAR() macro:
 *   Incrementes str & tok->char_offset.
 *   For convenience of existing conditionals, returns the old value of c (0 on eof)
 *   Implicit inputs:  c var
 */
#define ADVANCE_CHAR(str, tok) \
  ( ++(str), ((tok)->char_offset)++, c)


/* End optimization macro defs */


struct json_object* json_tokener_parse_ex(struct json_tokener *tok,
					  const char *str, int len)
{
  struct json_object *obj = NULL;
  char c = '\1';
#ifdef HAVE_USELOCALE
  locale_t oldlocale = uselocale(NULL);
  locale_t newloc;
#elif defined(HAVE_SETLOCALE)
  char *oldlocale = NULL;
#endif

  tok->char_offset = 0;
  tok->err = json_tokener_success;

  /* this interface is presently not 64-bit clean due to the int len argument
     and the internal printbuf interface that takes 32-bit int len arguments
     so the function limits the maximum string size to INT32_MAX (2GB).
     If the function is called with len == -1 then strlen is called to check
     the string length is less than INT32_MAX (2GB) */
  if ((len < -1) || (len == -1 && strlen(str) > INT32_MAX)) {
    tok->err = json_tokener_error_size;
    return NULL;
  }

#ifdef HAVE_USELOCALE
  {
    locale_t duploc = duplocale(oldlocale);
    newloc = newlocale(LC_NUMERIC, "C", duploc);
    // XXX at least Debian 8.4 has a bug in newlocale where it doesn't
    //  change the decimal separator unless you set LC_TIME!
    if (newloc)
    {
      duploc = newloc; // original duploc has been freed by newlocale()
      newloc = newlocale(LC_TIME, "C", duploc);
    }
    if (newloc == NULL)
    {
      freelocale(duploc);
      return NULL;
    }
    uselocale(newloc);
  }
#elif defined(HAVE_SETLOCALE)
  {
    char *tmplocale;
    tmplocale = setlocale(LC_NUMERIC, NULL);
    if (tmplocale) oldlocale = strdup(tmplocale);
    setlocale(LC_NUMERIC, "C");
  }
#endif

  while (PEEK_CHAR(c, tok)) {

  redo_char:
    switch(state) {

    case json_tokener_state_eatws:
      /* Advance until we change state */
      while (isspace((int)c)) {
	if ((!ADVANCE_CHAR(str, tok)) || (!PEEK_CHAR(c, tok)))
	  goto out;
      }
      if(c == '/' && !(tok->flags & JSON_TOKENER_STRICT)) {
	printbuf_reset(tok->pb);
	printbuf_memappend_fast(tok->pb, &c, 1);
	state = json_tokener_state_comment_start;
      } else {
	state = saved_state;
	goto redo_char;
      }
      break;

    case json_tokener_state_start:
      switch(c) {
      case '{':
	state = json_tokener_state_eatws;
	saved_state = json_tokener_state_object_field_start;
	current = json_object_new_object();
	if(current == NULL)
		goto out;
	break;
      case '[':
	state = json_tokener_state_eatws;
	saved_state = json_tokener_state_array;
	current = json_object_new_array();
	if(current == NULL)
		goto out;
	break;
      case 'I':
      case 'i':
	state = json_tokener_state_inf;
	printbuf_reset(tok->pb);
	tok->st_pos = 0;
	goto redo_char;
      case 'N':
      case 'n':
	state = json_tokener_state_null; // or NaN
	printbuf_reset(tok->pb);
	tok->st_pos = 0;
	goto redo_char;
      case '\'':
        if (tok->flags & JSON_TOKENER_STRICT) {
            /* in STRICT mode only double-quote are allowed */
            tok->err = json_tokener_error_parse_unexpected;
            goto out;
        }
      case '"':
	state = json_tokener_state_string;
	printbuf_reset(tok->pb);
	tok->quote_char = c;
	break;
      case 'T':
      case 't':
      case 'F':
      case 'f':
	state = json_tokener_state_boolean;
	printbuf_reset(tok->pb);
	tok->st_pos = 0;
	goto redo_char;
      case '0':
      case '1':
      case '2':
      case '3':
      case '4':
      case '5':
      case '6':
      case '7':
      case '8':
      case '9':
      case '-':
	state = json_tokener_state_number;
	printbuf_reset(tok->pb);
	tok->is_double = 0;
	goto redo_char;
      default:
	tok->err = json_tokener_error_parse_unexpected;
	goto out;
      }
      break;

    case json_tokener_state_finish:
      if(tok->depth == 0) goto out;
      obj = json_object_get(current);
      json_tokener_reset_level(tok, tok->depth);
      tok->depth--;
      goto redo_char;

    case json_tokener_state_inf: /* aka starts with 'i' */
      {
	size_t size_inf;
	int is_negative = 0;

	printbuf_memappend_fast(tok->pb, &c, 1);
	size_inf = json_min(tok->st_pos+1, json_inf_str_len);
	char *infbuf = tok->pb->buf;
	if (*infbuf == '-')
	{
		infbuf++;
		is_negative = 1;
	}
	if ((!(tok->flags & JSON_TOKENER_STRICT) &&
	          strncasecmp(json_inf_str, infbuf, size_inf) == 0) ||
	         (strncmp(json_inf_str, infbuf, size_inf) == 0)
	        )
	{
		if (tok->st_pos == json_inf_str_len)
		{
			current = json_object_new_double(is_negative
							 ? -INFINITY : INFINITY);
			if(current == NULL)
			    goto out;
			saved_state = json_tokener_state_finish;
			state = json_tokener_state_eatws;
			goto redo_char;
		}
	} else {
		tok->err = json_tokener_error_parse_unexpected;
		goto out;
	}
	tok->st_pos++;
      }
      break;
    case json_tokener_state_null: /* aka starts with 'n' */
      {
	int size;
	int size_nan;
	printbuf_memappend_fast(tok->pb, &c, 1);
	size = json_min(tok->st_pos+1, json_null_str_len);
	size_nan = json_min(tok->st_pos+1, json_nan_str_len);
	if((!(tok->flags & JSON_TOKENER_STRICT) &&
	  strncasecmp(json_null_str, tok->pb->buf, size) == 0)
	  || (strncmp(json_null_str, tok->pb->buf, size) == 0)
	  ) {
	  if (tok->st_pos == json_null_str_len) {
	    current = NULL;
	    saved_state = json_tokener_state_finish;
	    state = json_tokener_state_eatws;
	    goto redo_char;
	  }
	}
	else if ((!(tok->flags & JSON_TOKENER_STRICT) &&
	          strncasecmp(json_nan_str, tok->pb->buf, size_nan) == 0) ||
	         (strncmp(json_nan_str, tok->pb->buf, size_nan) == 0)
	        )
	{
		if (tok->st_pos == json_nan_str_len)
		{
			current = json_object_new_double(NAN);
			if (current == NULL)
			    goto out;
			saved_state = json_tokener_state_finish;
			state = json_tokener_state_eatws;
			goto redo_char;
		}
	} else {
	  tok->err = json_tokener_error_parse_null;
	  goto out;
	}
	tok->st_pos++;
      }
      break;

    case json_tokener_state_comment_start:
      if(c == '*') {
	state = json_tokener_state_comment;
      } else if(c == '/') {
	state = json_tokener_state_comment_eol;
      } else {
	tok->err = json_tokener_error_parse_comment;
	goto out;
      }
      printbuf_memappend_fast(tok->pb, &c, 1);
      break;

    case json_tokener_state_comment:
              {
          /* Advance until we change state */
          const char *case_start = str;
          while(c != '*') {
            if (!ADVANCE_CHAR(str, tok) || !PEEK_CHAR(c, tok)) {
              printbuf_memappend_fast(tok->pb, case_start, str-case_start);
              goto out;
            }
          }
          printbuf_memappend_fast(tok->pb, case_start, 1+str-case_start);
          state = json_tokener_state_comment_end;
        }
            break;

    case json_tokener_state_comment_eol:
      {
	/* Advance until we change state */
	const char *case_start = str;
	while(c != '\n') {
	  if (!ADVANCE_CHAR(str, tok) || !PEEK_CHAR(c, tok)) {
	    printbuf_memappend_fast(tok->pb, case_start, str-case_start);
	    goto out;
	  }
	}
	printbuf_memappend_fast(tok->pb, case_start, str-case_start);
	MC_DEBUG("json_tokener_comment: %s\n", tok->pb->buf);
	state = json_tokener_state_eatws;
      }
      break;

    case json_tokener_state_comment_end:
      printbuf_memappend_fast(tok->pb, &c, 1);
      if(c == '/') {
	MC_DEBUG("json_tokener_comment: %s\n", tok->pb->buf);
	state = json_tokener_state_eatws;
      } else {
	state = json_tokener_state_comment;
      }
      break;

    case json_tokener_state_string:
      {
	/* Advance until we change state */
	const char *case_start = str;
	while(1) {
	  if(c == tok->quote_char) {
	    printbuf_memappend_fast(tok->pb, case_start, str-case_start);
	    current = json_object_new_string_len(tok->pb->buf, tok->pb->bpos);
	    if(current == NULL)
		goto out;
	    saved_state = json_tokener_state_finish;
	    state = json_tokener_state_eatws;
	    break;
	  } else if(c == '\\') {
	    printbuf_memappend_fast(tok->pb, case_start, str-case_start);
	    saved_state = json_tokener_state_string;
	    state = json_tokener_state_string_escape;
	    break;
	  }
	  if (!ADVANCE_CHAR(str, tok) || !PEEK_CHAR(c, tok)) {
	    printbuf_memappend_fast(tok->pb, case_start, str-case_start);
	    goto out;
	  }
	}
      }
      break;

    case json_tokener_state_string_escape:
      switch(c) {
      case '"':
      case '\\':
      case '/':
	printbuf_memappend_fast(tok->pb, &c, 1);
	state = saved_state;
	break;
      case 'b':
      case 'n':
      case 'r':
      case 't':
      case 'f':
	if(c == 'b') printbuf_memappend_fast(tok->pb, "\b", 1);
	else if(c == 'n') printbuf_memappend_fast(tok->pb, "\n", 1);
	else if(c == 'r') printbuf_memappend_fast(tok->pb, "\r", 1);
	else if(c == 't') printbuf_memappend_fast(tok->pb, "\t", 1);
	else if(c == 'f') printbuf_memappend_fast(tok->pb, "\f", 1);
	state = saved_state;
	break;
      case 'u':
	tok->ucs_char = 0;
	tok->st_pos = 0;
	state = json_tokener_state_escape_unicode;
	break;
      default:
	tok->err = json_tokener_error_parse_string;
	goto out;
      }
      break;

    case json_tokener_state_escape_unicode:
	{
          unsigned int got_hi_surrogate = 0;

	  /* Handle a 4-byte sequence, or two sequences if a surrogate pair */
	  while(1) {
	    if (c && strchr(json_hex_chars, c)) {
	      tok->ucs_char += ((unsigned int)jt_hexdigit(c) << ((3-tok->st_pos++)*4));
	      if(tok->st_pos == 4) {
		unsigned char unescaped_utf[4];

                if (got_hi_surrogate) {
		  if (IS_LOW_SURROGATE(tok->ucs_char)) {
                    /* Recalculate the ucs_char, then fall thru to process normally */
                    tok->ucs_char = DECODE_SURROGATE_PAIR(got_hi_surrogate, tok->ucs_char);
                  } else {
                    /* Hi surrogate was not followed by a low surrogate */
                    /* Replace the hi and process the rest normally */
		    printbuf_memappend_fast(tok->pb, (char*)utf8_replacement_char, 3);
                  }
                  got_hi_surrogate = 0;
                }

		if (tok->ucs_char < 0x80) {
		  unescaped_utf[0] = tok->ucs_char;
		  printbuf_memappend_fast(tok->pb, (char*)unescaped_utf, 1);
		} else if (tok->ucs_char < 0x800) {
		  unescaped_utf[0] = 0xc0 | (tok->ucs_char >> 6);
		  unescaped_utf[1] = 0x80 | (tok->ucs_char & 0x3f);
		  printbuf_memappend_fast(tok->pb, (char*)unescaped_utf, 2);
		} else if (IS_HIGH_SURROGATE(tok->ucs_char)) {
                  /* Got a high surrogate.  Remember it and look for the
                   * the beginning of another sequence, which should be the
                   * low surrogate.
                   */
                  got_hi_surrogate = tok->ucs_char;
                  /* Not at end, and the next two chars should be "\u" */
                  if ((len == -1 || len > (tok->char_offset + 2)) &&
                      // str[0] != '0' &&  // implied by json_hex_chars, above.
                      (str[1] == '\\') &&
                      (str[2] == 'u'))
                  {
                /* Advance through the 16 bit surrogate, and move on to the
                 * next sequence. The next step is to process the following
                 * characters.
                 */
	            if( !ADVANCE_CHAR(str, tok) || !ADVANCE_CHAR(str, tok) ) {
                    printbuf_memappend_fast(tok->pb,
					    (char*) utf8_replacement_char, 3);
		    }
                    /* Advance to the first char of the next sequence and
                     * continue processing with the next sequence.
                     */
	            if (!ADVANCE_CHAR(str, tok) || !PEEK_CHAR(c, tok)) {
	              printbuf_memappend_fast(tok->pb,
					      (char*) utf8_replacement_char, 3);
	              goto out;
                    }
	            tok->ucs_char = 0;
                    tok->st_pos = 0;
                    continue; /* other json_tokener_state_escape_unicode */
                  } else {
                    /* Got a high surrogate without another sequence following
                     * it.  Put a replacement char in for the hi surrogate
                     * and pretend we finished.
                     */
		    printbuf_memappend_fast(tok->pb,
					    (char*) utf8_replacement_char, 3);
                  }
		} else if (IS_LOW_SURROGATE(tok->ucs_char)) {
                  /* Got a low surrogate not preceded by a high */
		  printbuf_memappend_fast(tok->pb, (char*)utf8_replacement_char, 3);
                } else if (tok->ucs_char < 0x10000) {
		  unescaped_utf[0] = 0xe0 | (tok->ucs_char >> 12);
		  unescaped_utf[1] = 0x80 | ((tok->ucs_char >> 6) & 0x3f);
		  unescaped_utf[2] = 0x80 | (tok->ucs_char & 0x3f);
		  printbuf_memappend_fast(tok->pb, (char*)unescaped_utf, 3);
		} else if (tok->ucs_char < 0x110000) {
		  unescaped_utf[0] = 0xf0 | ((tok->ucs_char >> 18) & 0x07);
		  unescaped_utf[1] = 0x80 | ((tok->ucs_char >> 12) & 0x3f);
		  unescaped_utf[2] = 0x80 | ((tok->ucs_char >> 6) & 0x3f);
		  unescaped_utf[3] = 0x80 | (tok->ucs_char & 0x3f);
		  printbuf_memappend_fast(tok->pb, (char*)unescaped_utf, 4);
		} else {
                  /* Don't know what we got--insert the replacement char */
		  printbuf_memappend_fast(tok->pb, (char*)utf8_replacement_char, 3);
                }
		state = saved_state;
		break;
	      }
	    } else {
	      tok->err = json_tokener_error_parse_string;
	      goto out;
	    }
	  if (!ADVANCE_CHAR(str, tok) || !PEEK_CHAR(c, tok)) {
            if (got_hi_surrogate) /* Clean up any pending chars */
	      printbuf_memappend_fast(tok->pb, (char*)utf8_replacement_char, 3);
	    goto out;
	  }
	}
      }
      break;

    case json_tokener_state_boolean:
      {
	int size1, size2;
	printbuf_memappend_fast(tok->pb, &c, 1);
	size1 = json_min(tok->st_pos+1, json_true_str_len);
	size2 = json_min(tok->st_pos+1, json_false_str_len);
	if((!(tok->flags & JSON_TOKENER_STRICT) &&
	  strncasecmp(json_true_str, tok->pb->buf, size1) == 0)
	  || (strncmp(json_true_str, tok->pb->buf, size1) == 0)
	  ) {
	  if(tok->st_pos == json_true_str_len) {
	    current = json_object_new_boolean(1);
	    if(current == NULL)
		goto out;
	    saved_state = json_tokener_state_finish;
	    state = json_tokener_state_eatws;
	    goto redo_char;
	  }
	} else if((!(tok->flags & JSON_TOKENER_STRICT) &&
	  strncasecmp(json_false_str, tok->pb->buf, size2) == 0)
	  || (strncmp(json_false_str, tok->pb->buf, size2) == 0)) {
	  if(tok->st_pos == json_false_str_len) {
	    current = json_object_new_boolean(0);
	    if(current == NULL)
		goto out;
	    saved_state = json_tokener_state_finish;
	    state = json_tokener_state_eatws;
	    goto redo_char;
	  }
	} else {
	  tok->err = json_tokener_error_parse_boolean;
	  goto out;
	}
	tok->st_pos++;
      }
      break;

    case json_tokener_state_number:
      {
	/* Advance until we change state */
	const char *case_start = str;
	int case_len=0;
	int is_exponent=0;
	int negativesign_next_possible_location=1;
	while(c && strchr(json_number_chars, c)) {
	  ++case_len;

	  /* non-digit characters checks */
	  /* note: since the main loop condition to get here was
	           an input starting with 0-9 or '-', we are
	           protected from input starting with '.' or
	           e/E. */
	  if (c == '.') {
	    if (tok->is_double != 0) {
	      /* '.' can only be found once, and out of the exponent part.
	         Thus, if the input is already flagged as double, it
	         is invalid. */
	      tok->err = json_tokener_error_parse_number;
	      goto out;
	    }
	    tok->is_double = 1;
	  }
	  if (c == 'e' || c == 'E') {
	    if (is_exponent != 0) {
	      /* only one exponent possible */
	      tok->err = json_tokener_error_parse_number;
	      goto out;
	    }
	    is_exponent = 1;
	    tok->is_double = 1;
	    /* the exponent part can begin with a negative sign */
	    negativesign_next_possible_location = case_len + 1;
	  }
	  if (c == '-' && case_len != negativesign_next_possible_location) {
	    /* If the negative sign is not where expected (ie
	       start of input or start of exponent part), the
	       input is invalid. */
	    tok->err = json_tokener_error_parse_number;
	    goto out;
	  }

	  if (!ADVANCE_CHAR(str, tok) || !PEEK_CHAR(c, tok)) {
	    printbuf_memappend_fast(tok->pb, case_start, case_len);
	    goto out;
	  }
	}
        if (case_len>0)
          printbuf_memappend_fast(tok->pb, case_start, case_len);

	// Check for -Infinity
	if (tok->pb->buf[0] == '-' && case_len == 1 &&
	    (c == 'i' || c == 'I'))
	{
		state = json_tokener_state_inf;
		goto redo_char;
	}
      }
      {
	int64_t num64;
	double  numd;
	if (!tok->is_double && json_parse_int64(tok->pb->buf, &num64) == 0) {
		if (num64 && tok->pb->buf[0]=='0' &&
		    (tok->flags & JSON_TOKENER_STRICT)) {
			/* in strict mode, number must not start with 0 */
			tok->err = json_tokener_error_parse_number;
			goto out;
		}
		current = json_object_new_int64(num64);
		if(current == NULL)
		    goto out;
	}
	else if(tok->is_double && json_parse_double(tok->pb->buf, &numd) == 0)
	{
          current = json_object_new_double_s(numd, tok->pb->buf);
	  if(current == NULL)
		goto out;
        } else {
          tok->err = json_tokener_error_parse_number;
          goto out;
        }
        saved_state = json_tokener_state_finish;
        state = json_tokener_state_eatws;
        goto redo_char;
      }
      break;

    case json_tokener_state_array_after_sep:
    case json_tokener_state_array:
      if(c == ']') {
	if (state == json_tokener_state_array_after_sep &&
	    (tok->flags & JSON_TOKENER_STRICT))
	  {
	    tok->err = json_tokener_error_parse_unexpected;
	    goto out;
	  }
	saved_state = json_tokener_state_finish;
	state = json_tokener_state_eatws;
      } else {
	if(tok->depth >= tok->max_depth-1) {
	  tok->err = json_tokener_error_depth;
	  goto out;
	}
	state = json_tokener_state_array_add;
	tok->depth++;
	json_tokener_reset_level(tok, tok->depth);
	goto redo_char;
      }
      break;

    case json_tokener_state_array_add:
      if( json_object_array_add(current, obj) != 0 )
        goto out;
      saved_state = json_tokener_state_array_sep;
      state = json_tokener_state_eatws;
      goto redo_char;

    case json_tokener_state_array_sep:
      if(c == ']') {
	saved_state = json_tokener_state_finish;
	state = json_tokener_state_eatws;
      } else if(c == ',') {
	saved_state = json_tokener_state_array_after_sep;
	state = json_tokener_state_eatws;
      } else {
	tok->err = json_tokener_error_parse_array;
	goto out;
      }
      break;

    case json_tokener_state_object_field_start:
    case json_tokener_state_object_field_start_after_sep:
      if(c == '}') {
		if (state == json_tokener_state_object_field_start_after_sep &&
		    (tok->flags & JSON_TOKENER_STRICT))
		{
			tok->err = json_tokener_error_parse_unexpected;
			goto out;
		}
	saved_state = json_tokener_state_finish;
	state = json_tokener_state_eatws;
      } else if (c == '"' || c == '\'') {
	tok->quote_char = c;
	printbuf_reset(tok->pb);
	state = json_tokener_state_object_field;
      } else {
	tok->err = json_tokener_error_parse_object_key_name;
	goto out;
      }
      break;

    case json_tokener_state_object_field:
      {
	/* Advance until we change state */
	const char *case_start = str;
	while(1) {
	  if(c == tok->quote_char) {
	    printbuf_memappend_fast(tok->pb, case_start, str-case_start);
	    obj_field_name = strdup(tok->pb->buf);
	    saved_state = json_tokener_state_object_field_end;
	    state = json_tokener_state_eatws;
	    break;
	  } else if(c == '\\') {
	    printbuf_memappend_fast(tok->pb, case_start, str-case_start);
	    saved_state = json_tokener_state_object_field;
	    state = json_tokener_state_string_escape;
	    break;
	  }
	  if (!ADVANCE_CHAR(str, tok) || !PEEK_CHAR(c, tok)) {
	    printbuf_memappend_fast(tok->pb, case_start, str-case_start);
	    goto out;
	  }
	}
      }
      break;

    case json_tokener_state_object_field_end:
      if(c == ':') {
	saved_state = json_tokener_state_object_value;
	state = json_tokener_state_eatws;
      } else {
	tok->err = json_tokener_error_parse_object_key_sep;
	goto out;
      }
      break;

    case json_tokener_state_object_value:
      if(tok->depth >= tok->max_depth-1) {
	tok->err = json_tokener_error_depth;
	goto out;
      }
      state = json_tokener_state_object_value_add;
      tok->depth++;
      json_tokener_reset_level(tok, tok->depth);
      goto redo_char;

    case json_tokener_state_object_value_add:
      json_object_object_add(current, obj_field_name, obj);
      free(obj_field_name);
      obj_field_name = NULL;
      saved_state = json_tokener_state_object_sep;
      state = json_tokener_state_eatws;
      goto redo_char;

    case json_tokener_state_object_sep:
      /* { */
      if(c == '}') {
	saved_state = json_tokener_state_finish;
	state = json_tokener_state_eatws;
      } else if(c == ',') {
	saved_state = json_tokener_state_object_field_start_after_sep;
	state = json_tokener_state_eatws;
      } else {
	tok->err = json_tokener_error_parse_object_value_sep;
	goto out;
      }
      break;

    }
    if (!ADVANCE_CHAR(str, tok))
      goto out;
  } /* while(POP_CHAR) */

 out:
  if (c &&
     (state == json_tokener_state_finish) &&
     (tok->depth == 0) &&
     (tok->flags & JSON_TOKENER_STRICT)) {
      /* unexpected char after JSON data */
      tok->err = json_tokener_error_parse_unexpected;
  }
  if (!c) { /* We hit an eof char (0) */
    if(state != json_tokener_state_finish &&
       saved_state != json_tokener_state_finish)
      tok->err = json_tokener_error_parse_eof;
  }

#ifdef HAVE_USELOCALE
  uselocale(oldlocale);
  freelocale(newloc); 
#elif defined(HAVE_SETLOCALE)
  setlocale(LC_NUMERIC, oldlocale);
  free(oldlocale);
#endif

  if (tok->err == json_tokener_success)
  {
    json_object *ret = json_object_get(current);
	int ii;

	/* Partially reset, so we parse additional objects on subsequent calls. */
    for(ii = tok->depth; ii >= 0; ii--)
      json_tokener_reset_level(tok, ii);
    return ret;
  }

  MC_DEBUG("json_tokener_parse_ex: error %s at offset %d\n",
	   json_tokener_errors[tok->err], tok->char_offset);
  return NULL;
}

void json_tokener_set_flags(struct json_tokener *tok, int flags)
{
	tok->flags = flags;
}