loader/cJSON.c

/*
  Copyright (c) 2009 Dave Gamble
  Copyright (c) 2015-2021 The Khronos Group Inc.
  Copyright (c) 2015-2021 Valve Corporation
  Copyright (c) 2015-2021 LunarG, Inc.

  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. */

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

#include "cJSON.h"

#include "allocation.h"

void *cJSON_malloc(const struct loader_instance *instance, size_t size) {
    return loader_instance_heap_alloc(instance, size, VK_SYSTEM_ALLOCATION_SCOPE_COMMAND);
}

void cJSON_free(const struct loader_instance *instance, void *pMemory) { loader_instance_heap_free(instance, pMemory); }

static const char *ep;

const char *cJSON_GetErrorPtr(void) { return ep; }

char *cJSON_strdup(const struct loader_instance *instance, const char *str) {
    size_t len;
    char *copy;

    len = strlen(str) + 1;
    if (!(copy = (char *)cJSON_malloc(instance, len))) return 0;
    memcpy(copy, str, len);
    return copy;
}

/* Internal constructor. */
cJSON *cJSON_New_Item(const struct loader_instance *instance) {
    cJSON *node = (cJSON *)cJSON_malloc(instance, sizeof(cJSON));
    if (node) memset(node, 0, sizeof(cJSON));
    return node;
}

/* Delete a cJSON structure. */
void cJSON_Delete(const struct loader_instance *instance, cJSON *c) {
    cJSON *next;
    while (c) {
        next = c->next;
        if (!(c->type & cJSON_IsReference) && c->child) cJSON_Delete(instance, c->child);
        if (!(c->type & cJSON_IsReference) && c->valuestring) cJSON_free(instance, c->valuestring);
        if (!(c->type & cJSON_StringIsConst) && c->string) cJSON_free(instance, c->string);
        cJSON_free(instance, c);
        c = next;
    }
}

void cJSON_Free(const struct loader_instance *instance, void *p) { cJSON_free(instance, p); }

/* Parse the input text to generate a number, and populate the result into item.
 */
const char *parse_number(cJSON *item, const char *num) {
    double n = 0, sign = 1, scale = 0;
    int subscale = 0, signsubscale = 1;

    if (*num == '-') sign = -1, num++; /* Has sign? */
    if (*num == '0') num++;            /* is zero */
    if (*num >= '1' && *num <= '9') do
            n = (n * 10.0) + (*num++ - '0');
        while (*num >= '0' && *num <= '9'); /* Number? */
    if (*num == '.' && num[1] >= '0' && num[1] <= '9') {
        num++;
        do n = (n * 10.0) + (*num++ - '0'), scale--;
        while (*num >= '0' && *num <= '9');
    }                               /* Fractional part? */
    if (*num == 'e' || *num == 'E') /* Exponent? */
    {
        num++;
        if (*num == '+')
            num++;
        else if (*num == '-')
            signsubscale = -1, num++;                                                   /* With sign? */
        while (*num >= '0' && *num <= '9') subscale = (subscale * 10) + (*num++ - '0'); /* Number? */
    }

    n = sign * n * pow(10.0, (scale + subscale * signsubscale)); /* number = +/-
                                                                    number.fraction *
                                                                    10^+/- exponent */

    item->valuedouble = n;
    item->valueint = (int)n;
    item->type = cJSON_Number;
    return num;
}

size_t pow2gt(size_t x) {
    --x;
    x |= x >> 1;
    x |= x >> 2;
    x |= x >> 4;
    x |= x >> 8;
    x |= x >> 16;
    return x + 1;
}

typedef struct {
    char *buffer;
    size_t length;
    size_t offset;
} printbuffer;

char *ensure(const struct loader_instance *instance, printbuffer *p, size_t needed) {
    char *newbuffer;
    size_t newsize;
    if (!p || !p->buffer) return 0;
    needed += p->offset;
    if (needed <= p->length) return p->buffer + p->offset;

    newsize = pow2gt(needed);
    newbuffer = (char *)cJSON_malloc(instance, newsize);
    if (!newbuffer) {
        cJSON_free(instance, p->buffer);
        p->length = 0, p->buffer = 0;
        return 0;
    }
    if (newbuffer) memcpy(newbuffer, p->buffer, p->length);
    cJSON_free(instance, p->buffer);
    p->length = newsize;
    p->buffer = newbuffer;
    return newbuffer + p->offset;
}

size_t cJSON_update(printbuffer *p) {
    char *str;
    if (!p || !p->buffer) return 0;
    str = p->buffer + p->offset;
    return p->offset + strlen(str);
}

/* Render the number nicely from the given item into a string. */
char *print_number(const struct loader_instance *instance, cJSON *item, printbuffer *p) {
    char *str = 0;
    double d = item->valuedouble;
    if (d == 0) {
        if (p)
            str = ensure(instance, p, 2);
        else
            str = (char *)cJSON_malloc(instance, 2); /* special case for 0. */
        if (str) strcpy(str, "0");
    } else if (fabs(((double)item->valueint) - d) <= DBL_EPSILON && d <= INT_MAX && d >= INT_MIN) {
        if (p)
            str = ensure(instance, p, 21);
        else
            str = (char *)cJSON_malloc(instance, 21); /* 2^64+1 can be represented in 21 chars. */
        if (str) sprintf(str, "%d", item->valueint);
    } else {
        if (p)
            str = ensure(instance, p, 64);
        else
            str = (char *)cJSON_malloc(instance, 64); /* This is a nice tradeoff. */
        if (str) {
            if (fabs(floor(d) - d) <= DBL_EPSILON && fabs(d) < 1.0e60)
                sprintf(str, "%.0f", d);
            else if (fabs(d) < 1.0e-6 || fabs(d) > 1.0e9)
                sprintf(str, "%e", d);
            else
                sprintf(str, "%f", d);
        }
    }
    return str;
}

unsigned parse_hex4(const char *str) {
    unsigned h = 0;
    if (*str >= '0' && *str <= '9')
        h += (*str) - '0';
    else if (*str >= 'A' && *str <= 'F')
        h += 10 + (*str) - 'A';
    else if (*str >= 'a' && *str <= 'f')
        h += 10 + (*str) - 'a';
    else
        return 0;
    h = h << 4;
    str++;
    if (*str >= '0' && *str <= '9')
        h += (*str) - '0';
    else if (*str >= 'A' && *str <= 'F')
        h += 10 + (*str) - 'A';
    else if (*str >= 'a' && *str <= 'f')
        h += 10 + (*str) - 'a';
    else
        return 0;
    h = h << 4;
    str++;
    if (*str >= '0' && *str <= '9')
        h += (*str) - '0';
    else if (*str >= 'A' && *str <= 'F')
        h += 10 + (*str) - 'A';
    else if (*str >= 'a' && *str <= 'f')
        h += 10 + (*str) - 'a';
    else
        return 0;
    h = h << 4;
    str++;
    if (*str >= '0' && *str <= '9')
        h += (*str) - '0';
    else if (*str >= 'A' && *str <= 'F')
        h += 10 + (*str) - 'A';
    else if (*str >= 'a' && *str <= 'f')
        h += 10 + (*str) - 'a';
    else
        return 0;
    return h;
}

/* Parse the input text into an unescaped cstring, and populate item. */
static const unsigned char firstByteMark[7] = {0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC};
const char *parse_string(const struct loader_instance *instance, cJSON *item, const char *str) {
    const char *ptr = str + 1;
    char *ptr2;
    char *out;
    int len = 0;
    unsigned uc, uc2;
    if (*str != '\"') {
        ep = str;
        return 0;
    } /* not a string! */

    while (*ptr != '\"' && *ptr && ++len)
        if (*ptr++ == '\\') ptr++; /* Skip escaped quotes. */

    out = (char *)cJSON_malloc(instance, len + 1); /* This is how long we need for the string, roughly. */
    if (!out) return 0;

    ptr = str + 1;
    ptr2 = out;
    while (*ptr != '\"' && *ptr) {
        if (*ptr != '\\')
            *ptr2++ = *ptr++;
        else {
            ptr++;
            switch (*ptr) {
                case 'b':
                    *ptr2++ = '\b';
                    break;
                case 'f':
                    *ptr2++ = '\f';
                    break;
                case 'n':
                    *ptr2++ = '\n';
                    break;
                case 'r':
                    *ptr2++ = '\r';
                    break;
                case 't':
                    *ptr2++ = '\t';
                    break;
                case 'u': /* transcode utf16 to utf8. */
                    uc = parse_hex4(ptr + 1);
                    ptr += 4; /* get the unicode char. */

                    if ((uc >= 0xDC00 && uc <= 0xDFFF) || uc == 0) break; /* check for invalid.	*/

                    if (uc >= 0xD800 && uc <= 0xDBFF) /* UTF16 surrogate pairs.	*/
                    {
                        if (ptr[1] != '\\' || ptr[2] != 'u') break; /* missing second-half of surrogate.	*/
                        uc2 = parse_hex4(ptr + 3);
                        ptr += 6;
                        if (uc2 < 0xDC00 || uc2 > 0xDFFF) break; /* invalid second-half of surrogate.	*/
                        uc = 0x10000 + (((uc & 0x3FF) << 10) | (uc2 & 0x3FF));
                    }

                    len = 4;
                    if (uc < 0x80)
                        len = 1;
                    else if (uc < 0x800)
                        len = 2;
                    else if (uc < 0x10000)
                        len = 3;
                    ptr2 += len;

                    switch (len) {
                        case 4:
                            *--ptr2 = ((uc | 0x80) & 0xBF);
                            uc >>= 6;
                            // fall through
                        case 3:
                            *--ptr2 = ((uc | 0x80) & 0xBF);
                            uc >>= 6;
                            // fall through
                        case 2:
                            *--ptr2 = ((uc | 0x80) & 0xBF);
                            uc >>= 6;
                            // fall through
                        case 1:
                            *--ptr2 = ((unsigned char)uc | firstByteMark[len]);
                    }
                    ptr2 += len;
                    break;
                default:
                    *ptr2++ = *ptr;
                    break;
            }
            ptr++;
        }
    }
    *ptr2 = 0;
    if (*ptr == '\"') ptr++;
    item->valuestring = out;
    item->type = cJSON_String;
    return ptr;
}

/* Render the cstring provided to an escaped version that can be printed. */
char *print_string_ptr(const struct loader_instance *instance, const char *str, printbuffer *p) {
    const char *ptr;
    char *ptr2;
    char *out;
    size_t len = 0, flag = 0;
    unsigned char token;

    for (ptr = str; *ptr; ptr++) flag |= ((*ptr > 0 && *ptr < 32) || (*ptr == '\"') || (*ptr == '\\')) ? 1 : 0;
    if (!flag) {
        len = ptr - str;
        if (p)
            out = ensure(instance, p, len + 3);
        else
            out = (char *)cJSON_malloc(instance, len + 3);
        if (!out) return 0;
        ptr2 = out;
        *ptr2++ = '\"';
        strcpy(ptr2, str);
        ptr2[len] = '\"';
        ptr2[len + 1] = 0;
        return out;
    }

    if (!str) {
        if (p)
            out = ensure(instance, p, 3);
        else
            out = (char *)cJSON_malloc(instance, 3);
        if (!out) return 0;
        strcpy(out, "\"\"");
        return out;
    }
    ptr = str;
    while ((token = *ptr) && ++len) {
        if (strchr("\"\\\b\f\n\r\t", token))
            len++;
        else if (token < 32)
            len += 5;
        ptr++;
    }

    if (p)
        out = ensure(instance, p, len + 3);
    else
        out = (char *)cJSON_malloc(instance, len + 3);
    if (!out) return 0;

    ptr2 = out;
    ptr = str;
    *ptr2++ = '\"';
    while (*ptr) {
        if ((unsigned char)*ptr > 31 && *ptr != '\"' && *ptr != '\\')
            *ptr2++ = *ptr++;
        else {
            switch (token = *ptr++) {
                case '\\':
                    *ptr2++ = '\\';
                    break;
                case '\"':
                    *ptr2++ = '\"';
                    break;
                case '\b':
                    *ptr2++ = '\b';
                    break;
                case '\f':
                    *ptr2++ = '\f';
                    break;
                case '\n':
                    *ptr2++ = '\n';
                    break;
                case '\r':
                    *ptr2++ = '\r';
                    break;
                case '\t':
                    *ptr2++ = '\t';
                    break;
                default:
                    sprintf(ptr2, "u%04x", token);
                    ptr2 += 5;
                    break; /* escape and print */
            }
        }
    }
    *ptr2++ = '\"';
    *ptr2++ = 0;
    return out;
}
/* Invote print_string_ptr (which is useful) on an item. */
char *print_string(const struct loader_instance *instance, cJSON *item, printbuffer *p) {
    return print_string_ptr(instance, item->valuestring, p);
}

/* Predeclare these prototypes. */
const char *parse_value(const struct loader_instance *instance, cJSON *item, const char *value);
char *print_value(const struct loader_instance *instance, cJSON *item, int depth, int fmt, printbuffer *p);
const char *parse_array(const struct loader_instance *instance, cJSON *item, const char *value);
char *print_array(const struct loader_instance *instance, cJSON *item, int depth, int fmt, printbuffer *p);
const char *parse_object(const struct loader_instance *instance, cJSON *item, const char *value);
char *print_object(const struct loader_instance *instance, cJSON *item, int depth, int fmt, printbuffer *p);

/* Utility to jump whitespace and cr/lf */
const char *skip(const char *in) {
    while (in && *in && (unsigned char)*in <= 32) in++;
    return in;
}

/* Parse an object - create a new root, and populate. */
cJSON *cJSON_ParseWithOpts(const struct loader_instance *instance, const char *value, const char **return_parse_end,
                           int require_null_terminated) {
    const char *end = 0;
    cJSON *c = cJSON_New_Item(instance);
    ep = 0;
    if (!c) return 0; /* memory fail */

    end = parse_value(instance, c, skip(value));
    if (!end) {
        cJSON_Delete(instance, c);
        return 0;
    } /* parse failure. ep is set. */

    /* if we require null-terminated JSON without appended garbage, skip and
     * then check for a null terminator */
    if (require_null_terminated) {
        end = skip(end);
        if (*end) {
            cJSON_Delete(instance, c);
            ep = end;
            return 0;
        }
    }
    if (return_parse_end) *return_parse_end = end;
    return c;
}
/* Default options for cJSON_Parse */
cJSON *cJSON_Parse(const struct loader_instance *instance, const char *value) { return cJSON_ParseWithOpts(instance, value, 0, 0); }

/* Render a cJSON item/entity/structure to text. */
char *cJSON_Print(const struct loader_instance *instance, cJSON *item) { return print_value(instance, item, 0, 1, 0); }
char *cJSON_PrintUnformatted(const struct loader_instance *instance, cJSON *item) { return print_value(instance, item, 0, 0, 0); }

char *cJSON_PrintBuffered(const struct loader_instance *instance, cJSON *item, int prebuffer, int fmt) {
    printbuffer p;
    p.buffer = (char *)cJSON_malloc(instance, prebuffer);
    p.length = prebuffer;
    p.offset = 0;
    return print_value(instance, item, 0, fmt, &p);
}

/* Parser core - when encountering text, process appropriately. */
const char *parse_value(const struct loader_instance *instance, cJSON *item, const char *value) {
    if (!value) return 0; /* Fail on null. */
    if (!strncmp(value, "null", 4)) {
        item->type = cJSON_NULL;
        return value + 4;
    }
    if (!strncmp(value, "false", 5)) {
        item->type = cJSON_False;
        return value + 5;
    }
    if (!strncmp(value, "true", 4)) {
        item->type = cJSON_True;
        item->valueint = 1;
        return value + 4;
    }
    if (*value == '\"') {
        return parse_string(instance, item, value);
    }
    if (*value == '-' || (*value >= '0' && *value <= '9')) {
        return parse_number(item, value);
    }
    if (*value == '[') {
        return parse_array(instance, item, value);
    }
    if (*value == '{') {
        return parse_object(instance, item, value);
    }

    ep = value;
    return 0; /* failure. */
}

/* Render a value to text. */
char *print_value(const struct loader_instance *instance, cJSON *item, int depth, int fmt, printbuffer *p) {
    char *out = 0;
    if (!item) return 0;
    if (p) {
        switch ((item->type) & 255) {
            case cJSON_NULL: {
                out = ensure(instance, p, 5);
                if (out) strcpy(out, "null");
                break;
            }
            case cJSON_False: {
                out = ensure(instance, p, 6);
                if (out) strcpy(out, "false");
                break;
            }
            case cJSON_True: {
                out = ensure(instance, p, 5);
                if (out) strcpy(out, "true");
                break;
            }
            case cJSON_Number:
                out = print_number(instance, item, p);
                break;
            case cJSON_String:
                out = print_string(instance, item, p);
                break;
            case cJSON_Array:
                out = print_array(instance, item, depth, fmt, p);
                break;
            case cJSON_Object:
                out = print_object(instance, item, depth, fmt, p);
                break;
        }
    } else {
        switch ((item->type) & 255) {
            case cJSON_NULL:
                out = cJSON_strdup(instance, "null");
                break;
            case cJSON_False:
                out = cJSON_strdup(instance, "false");
                break;
            case cJSON_True:
                out = cJSON_strdup(instance, "true");
                break;
            case cJSON_Number:
                out = print_number(instance, item, 0);
                break;
            case cJSON_String:
                out = print_string(instance, item, 0);
                break;
            case cJSON_Array:
                out = print_array(instance, item, depth, fmt, 0);
                break;
            case cJSON_Object:
                out = print_object(instance, item, depth, fmt, 0);
                break;
        }
    }
    return out;
}

/* Build an array from input text. */
const char *parse_array(const struct loader_instance *instance, cJSON *item, const char *value) {
    cJSON *child;
    if (*value != '[') {
        ep = value;
        return 0;
    } /* not an array! */

    item->type = cJSON_Array;
    value = skip(value + 1);
    if (*value == ']') return value + 1; /* empty array. */

    item->child = child = cJSON_New_Item(instance);
    if (!item->child) return 0;                              /* memory fail */
    value = skip(parse_value(instance, child, skip(value))); /* skip any spacing, get the value. */
    if (!value) return 0;

    while (*value == ',') {
        cJSON *new_item;
        if (!(new_item = cJSON_New_Item(instance))) return 0; /* memory fail */
        child->next = new_item;
        new_item->prev = child;
        child = new_item;
        value = skip(parse_value(instance, child, skip(value + 1)));
        if (!value) return 0; /* memory fail */
    }

    if (*value == ']') return value + 1; /* end of array */
    ep = value;
    return 0; /* malformed. */
}

/* Render an array to text */
char *print_array(const struct loader_instance *instance, cJSON *item, int depth, int fmt, printbuffer *p) {
    char **entries;
    char *out = 0, *ptr, *ret;
    size_t len = 5;
    cJSON *child = item->child;
    int numentries = 0, fail = 0, j = 0;
    size_t tmplen = 0, i = 0;

    /* How many entries in the array? */
    while (child) numentries++, child = child->next;
    /* Explicitly handle numentries==0 */
    if (!numentries) {
        if (p)
            out = ensure(instance, p, 3);
        else
            out = (char *)cJSON_malloc(instance, 3);
        if (out) strcpy(out, "[]");
        return out;
    }

    if (p) {
        /* Compose the output array. */
        i = p->offset;
        ptr = ensure(instance, p, 1);
        if (!ptr) return 0;
        *ptr = '[';
        p->offset++;
        child = item->child;
        while (child && !fail) {
            print_value(instance, child, depth + 1, fmt, p);
            p->offset = cJSON_update(p);
            if (child->next) {
                len = fmt ? 2 : 1;
                ptr = ensure(instance, p, len + 1);
                if (!ptr) return 0;
                *ptr++ = ',';
                if (fmt) *ptr++ = ' ';
                *ptr = 0;
                p->offset += len;
            }
            child = child->next;
        }
        ptr = ensure(instance, p, 2);
        if (!ptr) return 0;
        *ptr++ = ']';
        *ptr = 0;
        out = (p->buffer) + i;
    } else {
        /* Allocate an array to hold the values for each */
        entries = (char **)cJSON_malloc(instance, numentries * sizeof(char *));
        if (!entries) return 0;
        memset(entries, 0, numentries * sizeof(char *));
        /* Retrieve all the results: */
        child = item->child;
        while (child && !fail) {
            ret = print_value(instance, child, depth + 1, fmt, 0);
            entries[i++] = ret;
            if (ret)
                len += strlen(ret) + 2 + (fmt ? 1 : 0);
            else
                fail = 1;
            child = child->next;
        }

        /* If we didn't fail, try to malloc the output string */
        if (!fail) out = (char *)cJSON_malloc(instance, len);
        /* If that fails, we fail. */
        if (!out) fail = 1;

        /* Handle failure. */
        if (fail) {
            for (j = 0; j < numentries; j++)
                if (entries[j]) cJSON_free(instance, entries[j]);
            cJSON_free(instance, entries);
            return 0;
        }

        /* Compose the output array. */
        *out = '[';
        ptr = out + 1;
        *ptr = 0;
        for (j = 0; j < numentries; j++) {
            tmplen = strlen(entries[j]);
            memcpy(ptr, entries[j], tmplen);
            ptr += tmplen;
            if (j != numentries - 1) {
                *ptr++ = ',';
                if (fmt) *ptr++ = ' ';
                *ptr = 0;
            }
            cJSON_free(instance, entries[j]);
        }
        cJSON_free(instance, entries);
        *ptr++ = ']';
        *ptr++ = 0;
    }
    return out;
}

/* Build an object from the text. */
const char *parse_object(const struct loader_instance *instance, cJSON *item, const char *value) {
    cJSON *child;
    if (*value != '{') {
        ep = value;
        return 0;
    } /* not an object! */

    item->type = cJSON_Object;
    value = skip(value + 1);
    if (*value == '}') return value + 1; /* empty array. */

    item->child = child = cJSON_New_Item(instance);
    if (!item->child) return 0;
    value = skip(parse_string(instance, child, skip(value)));
    if (!value) return 0;
    child->string = child->valuestring;
    child->valuestring = 0;
    if (*value != ':') {
        ep = value;
        return 0;
    }                                                            /* fail! */
    value = skip(parse_value(instance, child, skip(value + 1))); /* skip any spacing, get the value. */
    if (!value) return 0;

    while (*value == ',') {
        cJSON *new_item;
        if (!(new_item = cJSON_New_Item(instance))) return 0; /* memory fail */
        child->next = new_item;
        new_item->prev = child;
        child = new_item;
        value = skip(parse_string(instance, child, skip(value + 1)));
        if (!value) return 0;
        child->string = child->valuestring;
        child->valuestring = 0;
        if (*value != ':') {
            ep = value;
            return 0;
        }                                                            /* fail! */
        value = skip(parse_value(instance, child, skip(value + 1))); /* skip any spacing, get the value. */
        if (!value) return 0;
    }

    if (*value == '}') return value + 1; /* end of array */
    ep = value;
    return 0; /* malformed. */
}

/* Render an object to text. */
char *print_object(const struct loader_instance *instance, cJSON *item, int depth, int fmt, printbuffer *p) {
    char **entries = 0, **names = 0;
    char *out = 0, *ptr, *ret, *str;
    int j;
    cJSON *child = item->child;
    int numentries = 0, fail = 0, k;
    size_t tmplen = 0, i = 0, len = 7;
    /* Count the number of entries. */
    while (child) numentries++, child = child->next;
    /* Explicitly handle empty object case */
    if (!numentries) {
        if (p)
            out = ensure(instance, p, fmt ? depth + 4 : 3);
        else
            out = (char *)cJSON_malloc(instance, fmt ? depth + 4 : 3);
        if (!out) return 0;
        ptr = out;
        *ptr++ = '{';
        if (fmt) {
            *ptr++ = '\n';
            for (j = 0; j < depth - 1; j++) *ptr++ = '\t';
        }
        *ptr++ = '}';
        *ptr++ = 0;
        return out;
    }
    if (p) {
        /* Compose the output: */
        i = p->offset;
        len = fmt ? 2 : 1;
        ptr = ensure(instance, p, len + 1);
        if (!ptr) return 0;
        *ptr++ = '{';
        if (fmt) *ptr++ = '\n';
        *ptr = 0;
        p->offset += len;
        child = item->child;
        depth++;
        while (child) {
            if (fmt) {
                ptr = ensure(instance, p, depth);
                if (!ptr) return 0;
                for (j = 0; j < depth; j++) *ptr++ = '\t';
                p->offset += depth;
            }
            print_string_ptr(instance, child->string, p);
            p->offset = cJSON_update(p);

            len = fmt ? 2 : 1;
            ptr = ensure(instance, p, len);
            if (!ptr) return 0;
            *ptr++ = ':';
            if (fmt) *ptr++ = '\t';
            p->offset += len;

            print_value(instance, child, depth, fmt, p);
            p->offset = cJSON_update(p);

            len = (fmt ? 1 : 0) + (child->next ? 1 : 0);
            ptr = ensure(instance, p, len + 1);
            if (!ptr) return 0;
            if (child->next) *ptr++ = ',';
            if (fmt) *ptr++ = '\n';
            *ptr = 0;
            p->offset += len;
            child = child->next;
        }
        ptr = ensure(instance, p, fmt ? (depth + 1) : 2);
        if (!ptr) return 0;
        if (fmt)
            for (j = 0; j < depth - 1; j++) *ptr++ = '\t';
        *ptr++ = '}';
        *ptr = 0;
        out = (p->buffer) + i;
    } else {
        /* Allocate space for the names and the objects */
        entries = (char **)cJSON_malloc(instance, numentries * sizeof(char *));
        if (!entries) return 0;
        names = (char **)cJSON_malloc(instance, numentries * sizeof(char *));
        if (!names) {
            cJSON_free(instance, entries);
            return 0;
        }
        memset(entries, 0, sizeof(char *) * numentries);
        memset(names, 0, sizeof(char *) * numentries);

        /* Collect all the results into our arrays: */
        child = item->child;
        depth++;
        if (fmt) len += depth;
        while (child) {
            names[i] = str = print_string_ptr(instance, child->string, 0);
            entries[i++] = ret = print_value(instance, child, depth, fmt, 0);
            if (str && ret)
                len += strlen(ret) + strlen(str) + 2 + (fmt ? 2 + depth : 0);
            else
                fail = 1;
            child = child->next;
        }

        /* Try to allocate the output string */
        if (!fail) out = (char *)cJSON_malloc(instance, len);
        if (!out) fail = 1;

        /* Handle failure */
        if (fail) {
            for (j = 0; j < numentries; j++) {
                if (names[i]) cJSON_free(instance, names[j]);
                if (entries[j]) cJSON_free(instance, entries[j]);
            }
            cJSON_free(instance, names);
            cJSON_free(instance, entries);
            return 0;
        }

        /* Compose the output: */
        *out = '{';
        ptr = out + 1;
        if (fmt) *ptr++ = '\n';
        *ptr = 0;
        for (j = 0; j < numentries; j++) {
            if (fmt)
                for (k = 0; k < depth; k++) *ptr++ = '\t';
            tmplen = strlen(names[j]);
            memcpy(ptr, names[j], tmplen);
            ptr += tmplen;
            *ptr++ = ':';
            if (fmt) *ptr++ = '\t';
            strcpy(ptr, entries[j]);
            ptr += strlen(entries[j]);
            if (j != numentries - 1) *ptr++ = ',';
            if (fmt) *ptr++ = '\n';
            *ptr = 0;
            cJSON_free(instance, names[j]);
            cJSON_free(instance, entries[j]);
        }

        cJSON_free(instance, names);
        cJSON_free(instance, entries);
        if (fmt)
            for (j = 0; j < depth - 1; j++) *ptr++ = '\t';
        *ptr++ = '}';
        *ptr++ = 0;
    }
    return out;
}

/* Get Array size/item / object item. */
int cJSON_GetArraySize(cJSON *array) {
    cJSON *c = array->child;
    int i = 0;
    while (c) i++, c = c->next;
    return i;
}
cJSON *cJSON_GetArrayItem(cJSON *array, int item) {
    cJSON *c = array->child;
    while (c && item > 0) item--, c = c->next;
    return c;
}
cJSON *cJSON_GetObjectItem(cJSON *object, const char *string) {
    cJSON *c = object->child;
    while (c && strcmp(c->string, string)) c = c->next;
    return c;
}

/* Utility for array list handling. */
void suffix_object(cJSON *prev, cJSON *item) {
    prev->next = item;
    item->prev = prev;
}
/* Utility for handling references. */
cJSON *create_reference(const struct loader_instance *instance, cJSON *item) {
    cJSON *ref = cJSON_New_Item(instance);
    if (!ref) return 0;
    memcpy(ref, item, sizeof(cJSON));
    ref->string = 0;
    ref->type |= cJSON_IsReference;
    ref->next = ref->prev = 0;
    return ref;
}

/* Add item to array/object. */
void cJSON_AddItemToArray(cJSON *array, cJSON *item) {
    cJSON *c = array->child;
    if (!item) return;
    if (!c) {
        array->child = item;
    } else {
        while (c && c->next) c = c->next;
        suffix_object(c, item);
    }
}
void cJSON_AddItemToObject(const struct loader_instance *instance, cJSON *object, const char *string, cJSON *item) {
    if (!item) return;
    if (item->string) cJSON_free(instance, item->string);
    item->string = cJSON_strdup(instance, string);
    cJSON_AddItemToArray(object, item);
}
void cJSON_AddItemToObjectCS(const struct loader_instance *instance, cJSON *object, const char *string, cJSON *item) {
    if (!item) return;
    if (!(item->type & cJSON_StringIsConst) && item->string) cJSON_free(instance, item->string);
    item->string = (char *)string;
    item->type |= cJSON_StringIsConst;
    cJSON_AddItemToArray(object, item);
}
void cJSON_AddItemReferenceToArray(const struct loader_instance *instance, cJSON *array, cJSON *item) {
    cJSON_AddItemToArray(array, create_reference(instance, item));
}
void cJSON_AddItemReferenceToObject(const struct loader_instance *instance, cJSON *object, const char *string, cJSON *item) {
    cJSON_AddItemToObject(instance, object, string, create_reference(instance, item));
}

cJSON *cJSON_DetachItemFromArray(cJSON *array, int which) {
    cJSON *c = array->child;
    while (c && which > 0) c = c->next, which--;
    if (!c) return 0;
    if (c->prev) c->prev->next = c->next;
    if (c->next) c->next->prev = c->prev;
    if (c == array->child) array->child = c->next;
    c->prev = c->next = 0;
    return c;
}
void cJSON_DeleteItemFromArray(const struct loader_instance *instance, cJSON *array, int which) {
    cJSON_Delete(instance, cJSON_DetachItemFromArray(array, which));
}
cJSON *cJSON_DetachItemFromObject(cJSON *object, const char *string) {
    int i = 0;
    cJSON *c = object->child;
    while (c && strcmp(c->string, string)) i++, c = c->next;
    if (c) return cJSON_DetachItemFromArray(object, i);
    return 0;
}
void cJSON_DeleteItemFromObject(const struct loader_instance *instance, cJSON *object, const char *string) {
    cJSON_Delete(instance, cJSON_DetachItemFromObject(object, string));
}

/* Replace array/object items with new ones. */
void cJSON_InsertItemInArray(cJSON *array, int which, cJSON *newitem) {
    cJSON *c = array->child;
    while (c && which > 0) c = c->next, which--;
    if (!c) {
        cJSON_AddItemToArray(array, newitem);
        return;
    }
    newitem->next = c;
    newitem->prev = c->prev;
    c->prev = newitem;
    if (c == array->child)
        array->child = newitem;
    else
        newitem->prev->next = newitem;
}
void cJSON_ReplaceItemInArray(const struct loader_instance *instance, cJSON *array, int which, cJSON *newitem) {
    cJSON *c = array->child;
    while (c && which > 0) c = c->next, which--;
    if (!c) return;
    newitem->next = c->next;
    newitem->prev = c->prev;
    if (newitem->next) newitem->next->prev = newitem;
    if (c == array->child)
        array->child = newitem;
    else
        newitem->prev->next = newitem;
    c->next = c->prev = 0;
    cJSON_Delete(instance, c);
}
void cJSON_ReplaceItemInObject(const struct loader_instance *instance, cJSON *object, const char *string, cJSON *newitem) {
    int i = 0;
    cJSON *c = object->child;
    while (c && strcmp(c->string, string)) i++, c = c->next;
    if (c) {
        newitem->string = cJSON_strdup(instance, string);
        cJSON_ReplaceItemInArray(instance, object, i, newitem);
    }
}

/* Create basic types: */
cJSON *cJSON_CreateNull(const struct loader_instance *instance) {
    cJSON *item = cJSON_New_Item(instance);
    if (item) item->type = cJSON_NULL;
    return item;
}
cJSON *cJSON_CreateTrue(const struct loader_instance *instance) {
    cJSON *item = cJSON_New_Item(instance);
    if (item) item->type = cJSON_True;
    return item;
}
cJSON *cJSON_CreateFalse(const struct loader_instance *instance) {
    cJSON *item = cJSON_New_Item(instance);
    if (item) item->type = cJSON_False;
    return item;
}
cJSON *cJSON_CreateBool(const struct loader_instance *instance, int b) {
    cJSON *item = cJSON_New_Item(instance);
    if (item) item->type = b ? cJSON_True : cJSON_False;
    return item;
}
cJSON *cJSON_CreateNumber(const struct loader_instance *instance, double num) {
    cJSON *item = cJSON_New_Item(instance);
    if (item) {
        item->type = cJSON_Number;
        item->valuedouble = num;
        item->valueint = (int)num;
    }
    return item;
}
cJSON *cJSON_CreateString(const struct loader_instance *instance, const char *string) {
    cJSON *item = cJSON_New_Item(instance);
    if (item) {
        item->type = cJSON_String;
        item->valuestring = cJSON_strdup(instance, string);
    }
    return item;
}
cJSON *cJSON_CreateArray(const struct loader_instance *instance) {
    cJSON *item = cJSON_New_Item(instance);
    if (item) item->type = cJSON_Array;
    return item;
}
cJSON *cJSON_CreateObject(const struct loader_instance *instance) {
    cJSON *item = cJSON_New_Item(instance);
    if (item) item->type = cJSON_Object;
    return item;
}

/* Create Arrays: */
cJSON *cJSON_CreateIntArray(const struct loader_instance *instance, const int *numbers, int count) {
    int i;
    cJSON *n = 0, *p = 0, *a = cJSON_CreateArray(instance);
    for (i = 0; a && i < count; i++) {
        n = cJSON_CreateNumber(instance, numbers[i]);
        if (!i)
            a->child = n;
        else
            suffix_object(p, n);
        p = n;
    }
    return a;
}
cJSON *cJSON_CreateFloatArray(const struct loader_instance *instance, const float *numbers, int count) {
    int i;
    cJSON *n = 0, *p = 0, *a = cJSON_CreateArray(instance);
    for (i = 0; a && i < count; i++) {
        n = cJSON_CreateNumber(instance, numbers[i]);
        if (!i)
            a->child = n;
        else
            suffix_object(p, n);
        p = n;
    }
    return a;
}
cJSON *cJSON_CreateDoubleArray(const struct loader_instance *instance, const double *numbers, int count) {
    int i;
    cJSON *n = 0, *p = 0, *a = cJSON_CreateArray(instance);
    for (i = 0; a && i < count; i++) {
        n = cJSON_CreateNumber(instance, numbers[i]);
        if (!i)
            a->child = n;
        else
            suffix_object(p, n);
        p = n;
    }
    return a;
}
cJSON *cJSON_CreateStringArray(const struct loader_instance *instance, const char **strings, int count) {
    int i;
    cJSON *n = 0, *p = 0, *a = cJSON_CreateArray(instance);
    for (i = 0; a && i < count; i++) {
        n = cJSON_CreateString(instance, strings[i]);
        if (!i)
            a->child = n;
        else
            suffix_object(p, n);
        p = n;
    }
    return a;
}

/* Duplication */
cJSON *cJSON_Duplicate(const struct loader_instance *instance, cJSON *item, int recurse) {
    cJSON *newitem, *cptr, *nptr = 0, *newchild;
    /* Bail on bad ptr */
    if (!item) return 0;
    /* Create new item */
    newitem = cJSON_New_Item(instance);
    if (!newitem) return 0;
    /* Copy over all vars */
    newitem->type = item->type & (~cJSON_IsReference), newitem->valueint = item->valueint, newitem->valuedouble = item->valuedouble;
    if (item->valuestring) {
        newitem->valuestring = cJSON_strdup(instance, item->valuestring);
        if (!newitem->valuestring) {
            cJSON_Delete(instance, newitem);
            return 0;
        }
    }
    if (item->string) {
        newitem->string = cJSON_strdup(instance, item->string);
        if (!newitem->string) {
            cJSON_Delete(instance, newitem);
            return 0;
        }
    }
    /* If non-recursive, then we're done! */
    if (!recurse) return newitem;
    /* Walk the ->next chain for the child. */
    cptr = item->child;
    while (cptr) {
        newchild = cJSON_Duplicate(instance, cptr, 1); /* Duplicate (with recurse) each item in the ->next chain */
        if (!newchild) {
            cJSON_Delete(instance, newitem);
            return 0;
        }
        if (nptr) {
            nptr->next = newchild, newchild->prev = nptr;
            nptr = newchild;
        } /* If newitem->child already set, then crosswire ->prev and ->next and
             move on */
        else {
            newitem->child = newchild;
            nptr = newchild;
        } /* Set newitem->child and move to it */
        cptr = cptr->next;
    }
    return newitem;
}

void cJSON_Minify(char *json) {
    char *into = json;
    while (*json) {
        if (*json == ' ')
            json++;
        else if (*json == '\t')
            json++; /* Whitespace characters. */
        else if (*json == '\r')
            json++;
        else if (*json == '\n')
            json++;
        else if (*json == '/' && json[1] == '/')
            while (*json && *json != '\n') json++; /* double-slash comments, to end of line. */
        else if (*json == '/' && json[1] == '*') {
            while (*json && !(*json == '*' && json[1] == '/')) json++;
            json += 2;
        } /* multiline comments. */
        else if (*json == '\"') {
            *into++ = *json++;
            while (*json && *json != '\"') {
                if (*json == '\\') *into++ = *json++;
                *into++ = *json++;
            }
            *into++ = *json++;
        } /* string literals, which are \" sensitive. */
        else
            *into++ = *json++; /* All other characters. */
    }
    *into = 0; /* and null-terminate. */
}