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/*
  Copyright (c) 2009-2017 Dave Gamble and cJSON contributors

  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
*/

/* cJSON */
/* JSON parser in C. */

/* disable warnings about old C89 functions in MSVC */
#if !defined(_CRT_SECURE_NO_DEPRECATE) && defined(_MSC_VER)
#define _CRT_SECURE_NO_DEPRECATE
#endif

#ifdef __GNUC__
#pragma GCC visibility push(default)
#endif
#if defined(_MSC_VER)
#pragma warning (push)
/* disable warning about single line comments in system headers */
#pragma warning (disable : 4001)
#endif

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

#ifdef ENABLE_LOCALES
#include <locale.h>
#endif

#if defined(_MSC_VER)
#pragma warning (pop)
#endif
#ifdef __GNUC__
#pragma GCC visibility pop
#endif

#include "cJSON.h"

/* define our own boolean type */
#define true ((cJSON_bool)1)
#define false ((cJSON_bool)0)

typedef struct {
    const unsigned char *json;
    size_t position;
} error;
static error global_error = { NULL, 0 };

CJSON_PUBLIC(const char *) cJSON_GetErrorPtr(void)
{
    return (const char*) (global_error.json + global_error.position);
}

CJSON_PUBLIC(char *) cJSON_GetStringValue(cJSON *item) {
    if (!cJSON_IsString(item)) {
        return NULL;
    }

    return item->valuestring;
}

/* This is a safeguard to prevent copy-pasters from using incompatible C and header files */
#if (CJSON_VERSION_MAJOR != 1) || (CJSON_VERSION_MINOR != 7) || (CJSON_VERSION_PATCH != 7)
    #error cJSON.h and cJSON.c have different versions. Make sure that both have the same.
#endif

CJSON_PUBLIC(const char*) cJSON_Version(void)
{
    static char version[15];
    sprintf(version, "%i.%i.%i", CJSON_VERSION_MAJOR, CJSON_VERSION_MINOR, CJSON_VERSION_PATCH);

    return version;
}

/* Case insensitive string comparison, doesn't consider two NULL pointers equal though */
static int case_insensitive_strcmp(const unsigned char *string1, const unsigned char *string2)
{
    if ((string1 == NULL) || (string2 == NULL))
    {
        return 1;
    }

    if (string1 == string2)
    {
        return 0;
    }

    for(; tolower(*string1) == tolower(*string2); (void)string1++, string2++)
    {
        if (*string1 == '\0')
        {
            return 0;
        }
    }

    return tolower(*string1) - tolower(*string2);
}

typedef struct internal_hooks
{
    void *(*allocate)(size_t size);
    void (*deallocate)(void *pointer);
    void *(*reallocate)(void *pointer, size_t size);
} internal_hooks;

#if defined(_MSC_VER)
/* work around MSVC error C2322: '...' address of dillimport '...' is not static */
static void *internal_malloc(size_t size)
{
    return malloc(size);
}
static void internal_free(void *pointer)
{
    free(pointer);
}
static void *internal_realloc(void *pointer, size_t size)
{
    return realloc(pointer, size);
}
#else
#define internal_malloc malloc
#define internal_free free
#define internal_realloc realloc
#endif

static internal_hooks global_hooks = { internal_malloc, internal_free, internal_realloc };

static unsigned char* cJSON_strdup(const unsigned char* string, const internal_hooks * const hooks)
{
    size_t length = 0;
    unsigned char *copy = NULL;

    if (string == NULL)
    {
        return NULL;
    }

    length = strlen((const char*)string) + sizeof("");
    copy = (unsigned char*)hooks->allocate(length);
    if (copy == NULL)
    {
        return NULL;
    }
    memcpy(copy, string, length);

    return copy;
}

CJSON_PUBLIC(void) cJSON_InitHooks(cJSON_Hooks* hooks)
{
    if (hooks == NULL)
    {
        /* Reset hooks */
        global_hooks.allocate = malloc;
        global_hooks.deallocate = free;
        global_hooks.reallocate = realloc;
        return;
    }

    global_hooks.allocate = malloc;
    if (hooks->malloc_fn != NULL)
    {
        global_hooks.allocate = hooks->malloc_fn;
    }

    global_hooks.deallocate = free;
    if (hooks->free_fn != NULL)
    {
        global_hooks.deallocate = hooks->free_fn;
    }

    /* use realloc only if both free and malloc are used */
    global_hooks.reallocate = NULL;
    if ((global_hooks.allocate == malloc) && (global_hooks.deallocate == free))
    {
        global_hooks.reallocate = realloc;
    }
}

/* Internal constructor. */
static cJSON *cJSON_New_Item(const internal_hooks * const hooks)
{
    cJSON* node = (cJSON*)hooks->allocate(sizeof(cJSON));
    if (node)
    {
        memset(node, '\0', sizeof(cJSON));
    }

    return node;
}

/* Delete a cJSON structure. */
CJSON_PUBLIC(void) cJSON_Delete(cJSON *item)
{
    cJSON *next = NULL;
    while (item != NULL)
    {
        next = item->next;
        if (!(item->type & cJSON_IsReference) && (item->child != NULL))
        {
            cJSON_Delete(item->child);
        }
        if (!(item->type & cJSON_IsReference) && (item->valuestring != NULL))
        {
            global_hooks.deallocate(item->valuestring);
        }
        if (!(item->type & cJSON_StringIsConst) && (item->string != NULL))
        {
            global_hooks.deallocate(item->string);
        }
        global_hooks.deallocate(item);
        item = next;
    }
}

/* get the decimal point character of the current locale */
static unsigned char get_decimal_point(void)
{
#ifdef ENABLE_LOCALES
    struct lconv *lconv = localeconv();
    return (unsigned char) lconv->decimal_point[0];
#else
    return '.';
#endif
}

typedef struct
{
    const unsigned char *content;
    size_t length;
    size_t offset;
    size_t depth; /* How deeply nested (in arrays/objects) is the input at the current offset. */
    internal_hooks hooks;
} parse_buffer;

/* check if the given size is left to read in a given parse buffer (starting with 1) */
#define can_read(buffer, size) ((buffer != NULL) && (((buffer)->offset + size) <= (buffer)->length))
/* check if the buffer can be accessed at the given index (starting with 0) */
#define can_access_at_index(buffer, index) ((buffer != NULL) && (((buffer)->offset + index) < (buffer)->length))
#define cannot_access_at_index(buffer, index) (!can_access_at_index(buffer, index))
/* get a pointer to the buffer at the position */
#define buffer_at_offset(buffer) ((buffer)->content + (buffer)->offset)

/* Parse the input text to generate a number, and populate the result into item. */
static cJSON_bool parse_number(cJSON * const item, parse_buffer * const input_buffer)
{
    double number = 0;
    unsigned char *after_end = NULL;
    unsigned char number_c_string[64];
    unsigned char decimal_point = get_decimal_point();
    size_t i = 0;

    if ((input_buffer == NULL) || (input_buffer->content == NULL))
    {
        return false;
    }

    /* copy the number into a temporary buffer and replace '.' with the decimal point
     * of the current locale (for strtod)
     * This also takes care of '\0' not necessarily being available for marking the end of the input */
    for (i = 0; (i < (sizeof(number_c_string) - 1)) && can_access_at_index(input_buffer, i); i++)
    {
        switch (buffer_at_offset(input_buffer)[i])
        {
            case '0':
            case '1':
            case '2':
            case '3':
            case '4':
            case '5':
            case '6':
            case '7':
            case '8':
            case '9':
            case '+':
            case '-':
            case 'e':
            case 'E':
                number_c_string[i] = buffer_at_offset(input_buffer)[i];
                break;

            case '.':
                number_c_string[i] = decimal_point;
                break;

            default:
                goto loop_end;
        }
    }
loop_end:
    number_c_string[i] = '\0';

    number = strtod((const char*)number_c_string, (char**)&after_end);
    if (number_c_string == after_end)
    {
        return false; /* parse_error */
    }

    item->valuedouble = number;

    /* use saturation in case of overflow */
    if (number >= INT_MAX)
    {
        item->valueint = INT_MAX;
    }
    else if (number <= INT_MIN)
    {
        item->valueint = INT_MIN;
    }
    else
    {
        item->valueint = (int)number;
    }

    item->type = cJSON_Number;

    input_buffer->offset += (size_t)(after_end - number_c_string);
    return true;
}

/* don't ask me, but the original cJSON_SetNumberValue returns an integer or double */
CJSON_PUBLIC(double) cJSON_SetNumberHelper(cJSON *object, double number)
{
    if (number >= INT_MAX)
    {
        object->valueint = INT_MAX;
    }
    else if (number <= INT_MIN)
    {
        object->valueint = INT_MIN;
    }
    else
    {
        object->valueint = (int)number;
    }

    return object->valuedouble = number;
}

typedef struct
{
    unsigned char *buffer;
    size_t length;
    size_t offset;
    size_t depth; /* current nesting depth (for formatted printing) */
    cJSON_bool noalloc;
    cJSON_bool format; /* is this print a formatted print */
    internal_hooks hooks;
} printbuffer;

/* realloc printbuffer if necessary to have at least "needed" bytes more */
static unsigned char* ensure(printbuffer * const p, size_t needed)
{
    unsigned char *newbuffer = NULL;
    size_t newsize = 0;

    if ((p == NULL) || (p->buffer == NULL))
    {
        return NULL;
    }

    if ((p->length > 0) && (p->offset >= p->length))
    {
        /* make sure that offset is valid */
        return NULL;
    }

    if (needed > INT_MAX)
    {
        /* sizes bigger than INT_MAX are currently not supported */
        return NULL;
    }

    needed += p->offset + 1;
    if (needed <= p->length)
    {
        return p->buffer + p->offset;
    }

    if (p->noalloc) {
        return NULL;
    }

    /* calculate new buffer size */
    if (needed > (INT_MAX / 2))
    {
        /* overflow of int, use INT_MAX if possible */
        if (needed <= INT_MAX)
        {
            newsize = INT_MAX;
        }
        else
        {
            return NULL;
        }
    }
    else
    {
        newsize = needed * 2;
    }

    if (p->hooks.reallocate != NULL)
    {
        /* reallocate with realloc if available */
        newbuffer = (unsigned char*)p->hooks.reallocate(p->buffer, newsize);
        if (newbuffer == NULL)
        {
            p->hooks.deallocate(p->buffer);
            p->length = 0;
            p->buffer = NULL;

            return NULL;
        }
    }
    else
    {
        /* otherwise reallocate manually */
        newbuffer = (unsigned char*)p->hooks.allocate(newsize);
        if (!newbuffer)
        {
            p->hooks.deallocate(p->buffer);
            p->length = 0;
            p->buffer = NULL;

            return NULL;
        }
        if (newbuffer)
        {
            memcpy(newbuffer, p->buffer, p->offset + 1);
        }
        p->hooks.deallocate(p->buffer);
    }
    p->length = newsize;
    p->buffer = newbuffer;

    return newbuffer + p->offset;
}

/* calculate the new length of the string in a printbuffer and update the offset */
static void update_offset(printbuffer * const buffer)
{
    const unsigned char *buffer_pointer = NULL;
    if ((buffer == NULL) || (buffer->buffer == NULL))
    {
        return;
    }
    buffer_pointer = buffer->buffer + buffer->offset;

    buffer->offset += strlen((const char*)buffer_pointer);
}

/* Render the number nicely from the given item into a string. */
static cJSON_bool print_number(const cJSON * const item, printbuffer * const output_buffer)
{
    unsigned char *output_pointer = NULL;
    double d = item->valuedouble;
    int length = 0;
    size_t i = 0;
    unsigned char number_buffer[26]; /* temporary buffer to print the number into */
    unsigned char decimal_point = get_decimal_point();
    double test;

    if (output_buffer == NULL)
    {
        return false;
    }

    /* This checks for NaN and Infinity */
    if ((d * 0) != 0)
    {
        length = sprintf((char*)number_buffer, "null");
    }
    else
    {
        /* Try 15 decimal places of precision to avoid nonsignificant nonzero digits */
        length = sprintf((char*)number_buffer, "%1.15g", d);

        /* Check whether the original double can be recovered */
        if ((sscanf((char*)number_buffer, "%lg", &test) != 1) || ((double)test != d))
        {
            /* If not, print with 17 decimal places of precision */
            length = sprintf((char*)number_buffer, "%1.17g", d);
        }
    }

    /* sprintf failed or buffer overrun occured */
    if ((length < 0) || (length > (int)(sizeof(number_buffer) - 1)))
    {
        return false;
    }

    /* reserve appropriate space in the output */
    output_pointer = ensure(output_buffer, (size_t)length + sizeof(""));
    if (output_pointer == NULL)
    {
        return false;
    }

    /* copy the printed number to the output and replace locale
     * dependent decimal point with '.' */
    for (i = 0; i < ((size_t)length); i++)
    {
        if (number_buffer[i] == decimal_point)
        {
            output_pointer[i] = '.';
            continue;
        }

        output_pointer[i] = number_buffer[i];
    }
    output_pointer[i] = '\0';

    output_buffer->offset += (size_t)length;

    return true;
}

/* parse 4 digit hexadecimal number */
static unsigned parse_hex4(const unsigned char * const input)
{
    unsigned int h = 0;
    size_t i = 0;

    for (i = 0; i < 4; i++)
    {
        /* parse digit */
        if ((input[i] >= '0') && (input[i] <= '9'))
        {
            h += (unsigned int) input[i] - '0';
        }
        else if ((input[i] >= 'A') && (input[i] <= 'F'))
        {
            h += (unsigned int) 10 + input[i] - 'A';
        }
        else if ((input[i] >= 'a') && (input[i] <= 'f'))
        {
            h += (unsigned int) 10 + input[i] - 'a';
        }
        else /* invalid */
        {
            return 0;
        }

        if (i < 3)
        {
            /* shift left to make place for the next nibble */
            h = h << 4;
        }
    }

    return h;
}

/* converts a UTF-16 literal to UTF-8
 * A literal can be one or two sequences of the form \uXXXX */
static unsigned char utf16_literal_to_utf8(const unsigned char * const input_pointer, const unsigned char * const input_end, unsigned char **output_pointer)
{
    long unsigned int codepoint = 0;
    unsigned int first_code = 0;
    const unsigned char *first_sequence = input_pointer;
    unsigned char utf8_length = 0;
    unsigned char utf8_position = 0;
    unsigned char sequence_length = 0;
    unsigned char first_byte_mark = 0;

    if ((input_end - first_sequence) < 6)
    {
        /* input ends unexpectedly */
        goto fail;
    }

    /* get the first utf16 sequence */
    first_code = parse_hex4(first_sequence + 2);

    /* check that the code is valid */
    if (((first_code >= 0xDC00) && (first_code <= 0xDFFF)))
    {
        goto fail;
    }

    /* UTF16 surrogate pair */
    if ((first_code >= 0xD800) && (first_code <= 0xDBFF))
    {
        const unsigned char *second_sequence = first_sequence + 6;
        unsigned int second_code = 0;
        sequence_length = 12; /* \uXXXX\uXXXX */

        if ((input_end - second_sequence) < 6)
        {
            /* input ends unexpectedly */
            goto fail;
        }

        if ((second_sequence[0] != '\\') || (second_sequence[1] != 'u'))
        {
            /* missing second half of the surrogate pair */
            goto fail;
        }

        /* get the second utf16 sequence */
        second_code = parse_hex4(second_sequence + 2);
        /* check that the code is valid */
        if ((second_code < 0xDC00) || (second_code > 0xDFFF))
        {
            /* invalid second half of the surrogate pair */
            goto fail;
        }


        /* calculate the unicode codepoint from the surrogate pair */
        codepoint = 0x10000 + (((first_code & 0x3FF) << 10) | (second_code & 0x3FF));
    }
    else
    {
        sequence_length = 6; /* \uXXXX */
        codepoint = first_code;
    }

    /* encode as UTF-8
     * takes at maximum 4 bytes to encode:
     * 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */
    if (codepoint < 0x80)
    {
        /* normal ascii, encoding 0xxxxxxx */
        utf8_length = 1;
    }
    else if (codepoint < 0x800)
    {
        /* two bytes, encoding 110xxxxx 10xxxxxx */
        utf8_length = 2;
        first_byte_mark = 0xC0; /* 11000000 */
    }
    else if (codepoint < 0x10000)
    {
        /* three bytes, encoding 1110xxxx 10xxxxxx 10xxxxxx */
        utf8_length = 3;
        first_byte_mark = 0xE0; /* 11100000 */
    }
    else if (codepoint <= 0x10FFFF)
    {
        /* four bytes, encoding 1110xxxx 10xxxxxx 10xxxxxx 10xxxxxx */
        utf8_length = 4;
        first_byte_mark = 0xF0; /* 11110000 */
    }
    else
    {
        /* invalid unicode codepoint */
        goto fail;
    }

    /* encode as utf8 */
    for (utf8_position = (unsigned char)(utf8_length - 1); utf8_position > 0; utf8_position--)
    {
        /* 10xxxxxx */
        (*output_pointer)[utf8_position] = (unsigned char)((codepoint | 0x80) & 0xBF);
        codepoint >>= 6;
    }
    /* encode first byte */
    if (utf8_length > 1)
    {
        (*output_pointer)[0] = (unsigned char)((codepoint | first_byte_mark) & 0xFF);
    }
    else
    {
        (*output_pointer)[0] = (unsigned char)(codepoint & 0x7F);
    }

    *output_pointer += utf8_length;

    return sequence_length;

fail:
    return 0;
}

/* Parse the input text into an unescaped cinput, and populate item. */
static cJSON_bool parse_string(cJSON * const item, parse_buffer * const input_buffer)
{
    const unsigned char *input_pointer = buffer_at_offset(input_buffer) + 1;
    const unsigned char *input_end = buffer_at_offset(input_buffer) + 1;
    unsigned char *output_pointer = NULL;
    unsigned char *output = NULL;

    /* not a string */
    if (buffer_at_offset(input_buffer)[0] != '\"')
    {
        goto fail;
    }

    {
        /* calculate approximate size of the output (overestimate) */
        size_t allocation_length = 0;
        size_t skipped_bytes = 0;
        while (((size_t)(input_end - input_buffer->content) < input_buffer->length) && (*input_end != '\"'))
        {
            /* is escape sequence */
            if (input_end[0] == '\\')
            {
                if ((size_t)(input_end + 1 - input_buffer->content) >= input_buffer->length)
                {
                    /* prevent buffer overflow when last input character is a backslash */
                    goto fail;
                }
                skipped_bytes++;
                input_end++;
            }
            input_end++;
        }
        if (((size_t)(input_end - input_buffer->content) >= input_buffer->length) || (*input_end != '\"'))
        {
            goto fail; /* string ended unexpectedly */
        }

        /* This is at most how much we need for the output */
        allocation_length = (size_t) (input_end - buffer_at_offset(input_buffer)) - skipped_bytes;
        output = (unsigned char*)input_buffer->hooks.allocate(allocation_length + sizeof(""));
        if (output == NULL)
        {
            goto fail; /* allocation failure */
        }
    }

    output_pointer = output;
    /* loop through the string literal */
    while (input_pointer < input_end)
    {
        if (*input_pointer != '\\')
        {
            *output_pointer++ = *input_pointer++;
        }
        /* escape sequence */
        else
        {
            unsigned char sequence_length = 2;
            if ((input_end - input_pointer) < 1)
            {
                goto fail;
            }

            switch (input_pointer[1])
            {
                case 'b':
                    *output_pointer++ = '\b';
                    break;
                case 'f':
                    *output_pointer++ = '\f';
                    break;
                case 'n':
                    *output_pointer++ = '\n';
                    break;
                case 'r':
                    *output_pointer++ = '\r';
                    break;
                case 't':
                    *output_pointer++ = '\t';
                    break;
                case '\"':
                case '\\':
                case '/':
                    *output_pointer++ = input_pointer[1];
                    break;

                /* UTF-16 literal */
                case 'u':
                    sequence_length = utf16_literal_to_utf8(input_pointer, input_end, &output_pointer);
                    if (sequence_length == 0)
                    {
                        /* failed to convert UTF16-literal to UTF-8 */
                        goto fail;
                    }
                    break;

                default:
                    goto fail;
            }
            input_pointer += sequence_length;
        }
    }

    /* zero terminate the output */
    *output_pointer = '\0';

    item->type = cJSON_String;
    item->valuestring = (char*)output;

    input_buffer->offset = (size_t) (input_end - input_buffer->content);
    input_buffer->offset++;

    return true;

fail:
    if (output != NULL)
    {
        input_buffer->hooks.deallocate(output);
    }

    if (input_pointer != NULL)
    {
        input_buffer->offset = (size_t)(input_pointer - input_buffer->content);
    }

    return false;
}

/* Render the cstring provided to an escaped version that can be printed. */
static cJSON_bool print_string_ptr(const unsigned char * const input, printbuffer * const output_buffer)
{
    const unsigned char *input_pointer = NULL;
    unsigned char *output = NULL;
    unsigned char *output_pointer = NULL;
    size_t output_length = 0;
    /* numbers of additional characters needed for escaping */
    size_t escape_characters = 0;

    if (output_buffer == NULL)
    {
        return false;
    }

    /* empty string */
    if (input == NULL)
    {
        output = ensure(output_buffer, sizeof("\"\""));
        if (output == NULL)
        {
            return false;
        }
        strcpy((char*)output, "\"\"");

        return true;
    }

    /* set "flag" to 1 if something needs to be escaped */
    for (input_pointer = input; *input_pointer; input_pointer++)
    {
        switch (*input_pointer)
        {
            case '\"':
            case '\\':
            case '\b':
            case '\f':
            case '\n':
            case '\r':
            case '\t':
                /* one character escape sequence */
                escape_characters++;
                break;
            default:
                if (*input_pointer < 32)
                {
                    /* UTF-16 escape sequence uXXXX */
                    escape_characters += 5;
                }
                break;
        }
    }
    output_length = (size_t)(input_pointer - input) + escape_characters;

    output = ensure(output_buffer, output_length + sizeof("\"\""));
    if (output == NULL)
    {
        return false;
    }

    /* no characters have to be escaped */
    if (escape_characters == 0)
    {
        output[0] = '\"';
        memcpy(output + 1, input, output_length);
        output[output_length + 1] = '\"';
        output[output_length + 2] = '\0';

        return true;
    }

    output[0] = '\"';
    output_pointer = output + 1;
    /* copy the string */
    for (input_pointer = input; *input_pointer != '\0'; (void)input_pointer++, output_pointer++)
    {
        if ((*input_pointer > 31) && (*input_pointer != '\"') && (*input_pointer != '\\'))
        {
            /* normal character, copy */
            *output_pointer = *input_pointer;
        }
        else
        {
            /* character needs to be escaped */
            *output_pointer++ = '\\';
            switch (*input_pointer)
            {
                case '\\':
                    *output_pointer = '\\';
                    break;
                case '\"':
                    *output_pointer = '\"';
                    break;
                case '\b':
                    *output_pointer = 'b';
                    break;
                case '\f':
                    *output_pointer = 'f';
                    break;
                case '\n':
                    *output_pointer = 'n';
                    break;
                case '\r':
                    *output_pointer = 'r';
                    break;
                case '\t':
                    *output_pointer = 't';
                    break;
                default:
                    /* escape and print as unicode codepoint */
                    sprintf((char*)output_pointer, "u%04x", *input_pointer);
                    output_pointer += 4;
                    break;
            }
        }
    }
    output[output_length + 1] = '\"';
    output[output_length + 2] = '\0';

    return true;
}

/* Invoke print_string_ptr (which is useful) on an item. */
static cJSON_bool print_string(const cJSON * const item, printbuffer * const p)
{
    return print_string_ptr((unsigned char*)item->valuestring, p);
}

/* Predeclare these prototypes. */
static cJSON_bool parse_value(cJSON * const item, parse_buffer * const input_buffer);
static cJSON_bool print_value(const cJSON * const item, printbuffer * const output_buffer);
static cJSON_bool parse_array(cJSON * const item, parse_buffer * const input_buffer);
static cJSON_bool print_array(const cJSON * const item, printbuffer * const output_buffer);
static cJSON_bool parse_object(cJSON * const item, parse_buffer * const input_buffer);
static cJSON_bool print_object(const cJSON * const item, printbuffer * const output_buffer);

/* Utility to jump whitespace and cr/lf */
static parse_buffer *buffer_skip_whitespace(parse_buffer * const buffer)
{
    if ((buffer == NULL) || (buffer->content == NULL))
    {
        return NULL;
    }

    while (can_access_at_index(buffer, 0) && (buffer_at_offset(buffer)[0] <= 32))
    {
       buffer->offset++;
    }

    if (buffer->offset == buffer->length)
    {
        buffer->offset--;
    }

    return buffer;
}

/* skip the UTF-8 BOM (byte order mark) if it is at the beginning of a buffer */
static parse_buffer *skip_utf8_bom(parse_buffer * const buffer)
{
    if ((buffer == NULL) || (buffer->content == NULL) || (buffer->offset != 0))
    {
        return NULL;
    }

    if (can_access_at_index(buffer, 4) && (strncmp((const char*)buffer_at_offset(buffer), "\xEF\xBB\xBF", 3) == 0))
    {
        buffer->offset += 3;
    }

    return buffer;
}

/* Parse an object - create a new root, and populate. */
CJSON_PUBLIC(cJSON *) cJSON_ParseWithOpts(const char *value, const char **return_parse_end, cJSON_bool require_null_terminated)