cJSON source code reading

JSON

cJSON.h

/* cJSON Types: */
#define cJSON_False  (1 << 0)
#define cJSON_True   (1 << 1)
#define cJSON_NULL   (1 << 2)
#define cJSON_Number (1 << 3)
#define cJSON_String (1 << 4)
#define cJSON_Array  (1 << 5)
#define cJSON_Object (1 << 6)

#define cJSON_IsReference 256
#define cJSON_StringIsConst 512

/* The cJSON structure: */
typedef struct cJSON {
struct cJSON *next,*prev;	/* next/prev allow you to walk array/object chains. Alternatively, use GetArraySize/GetArrayItem/GetObjectItem */
struct cJSON *child;		/* An array or object item will have a child pointer pointing to a chain of the items in the array/object. */

int type;					/* The type of the item, as above. */

char *valuestring;			/* The item's string, if type==cJSON_String */
int valueint;				/* The item's number, if type==cJSON_Number */
double valuedouble;			/* The item's number, if type==cJSON_Number */

char *string;				/* The item's name string, if this item is the child of, or is in the list of subitems of an object. */
} cJSON;

/* You can customize memory allocation and deallocation */
typedef struct cJSON_Hooks {
void *(*malloc_fn)(size_t sz);
void (*free_fn)(void *ptr);
} cJSON_Hooks;

cJSON.c

/* Memory management */
static void *(*cJSON_malloc)(size_t sz) = malloc;
static void (*cJSON_free)(void *ptr) = free;

void cJSON_InitHooks(cJSON_Hooks* hooks)
{
if (!hooks) { /* Reset hooks */
cJSON_malloc = malloc;
cJSON_free = free;
return;
}

cJSON_malloc = (hooks->malloc_fn)?hooks->malloc_fn:malloc;
cJSON_free	 = (hooks->free_fn)?hooks->free_fn:free;
}

/* Internal constructor. */
static cJSON *cJSON_New_Item(void)
{
cJSON* node = (cJSON*)cJSON_malloc(sizeof(cJSON));
if (node) memset(node,0,sizeof(cJSON));
return node;
}

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

/* String utility functions */
static const char *global_ep;

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

static int cJSON_strcasecmp(const char *s1,const char *s2)
{
if (!s1) return (s1==s2)?0:1;if (!s2) return 1;
for(; tolower(*s1) == tolower(*s2); ++s1, ++s2)	if(*s1 == 0)	return 0;
return tolower(*(const unsigned char *)s1) - tolower(*(const unsigned char *)s2);
}

static char* cJSON_strdup(const char* str)
{
size_t len;
char* copy;

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

/* Return the minimum pow(2, n) > x */
static int pow2gt (int x)	{	--x;	x|=x>>1;	x|=x>>2;	x|=x>>4;	x|=x>>8;	x|=x>>16;	return x+1;	}

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

static char* ensure(printbuffer *p,int needed)
{
char *newbuffer;int 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(newsize);
if (!newbuffer) {cJSON_free(p->buffer);p->length=0,p->buffer=0;return 0;}
if (newbuffer) memcpy(newbuffer,p->buffer,p->length);
cJSON_free(p->buffer);
p->length=newsize;
p->buffer=newbuffer;
return newbuffer+p->offset;
}

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

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

static 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;
}

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

/* Parse and print number */
/* Parse the input text to generate a number, and populate the result into item. */
static 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;
}

/* Render the number nicely from the given item into a string. */
static char *print_number(cJSON *item,printbuffer *p)
{
char *str=0;
double d=item->valuedouble;
if (d==0)
{
if (p)	str=ensure(p,2);
else	str=(char*)cJSON_malloc(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(p,21);
else	str=(char*)cJSON_malloc(21);	/* 2^64+1 can be represented in 21 chars. */
if (str)	sprintf(str,"%d",item->valueint);
}
else
{
if (p)	str=ensure(p,64);
else	str=(char*)cJSON_malloc(64);	/* This is a nice tradeoff. */
if (str)
{
if (d*0!=0)													sprintf(str,"null");	/* This checks for NaN and Infinity */
else 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;
}

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

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

out=(char*)cJSON_malloc(len+1);	/* This is how long we need for the string, roughly. */
if (!out) return 0;
item->valuestring=out; /* assign here so out will be deleted during cJSON_Delete() later */
item->type=cJSON_String;

ptr=str+1;ptr2=out;
while (ptr < end_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 (ptr >= end_ptr) {*ep=str;return 0;}	/* invalid */

if ((uc>=0xDC00 && uc<=0xDFFF) || uc==0)    {*ep=str;return 0;}	/* check for invalid.   */

if (uc>=0xD800 && uc<=0xDBFF)	/* UTF16 surrogate pairs.	*/
{
if (ptr+6 > end_ptr)    {*ep=str;return 0;}	/* invalid */
if (ptr[1]!='\\' || ptr[2]!='u')    {*ep=str;return 0;}	/* missing second-half of surrogate.    */
uc2=parse_hex4(ptr+3);ptr+=6;
if (uc2<0xDC00 || uc2>0xDFFF)       {*ep=str;return 0;}	/* 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;
case 3: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6;
case 2: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6;
case 1: *--ptr2 =(uc | firstByteMark[len]);
}
ptr2+=len;
break;
default:  *ptr2++=*ptr; break;
}
ptr++;
}
}
*ptr2=0;
if (*ptr=='\"') ptr++;
return ptr;
}

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

if (!str)
{
if (p)	out=ensure(p,3);
else	out=(char*)cJSON_malloc(3);
if (!out) return 0;
strcpy(out,"\"\"");
return out;
}

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

ptr2=out;ptr=str;
*ptr2++='\"';
while (*ptr)
{
if ((unsigned char)*ptr>31 && *ptr!='\"' && *ptr!='\\') *ptr2++=*ptr++;
else
{
*ptr2++='\\';
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. */
static char *print_string(cJSON *item,printbuffer *p)	{return print_string_ptr(item->valuestring,p);}

/* Parse and print value */
/* Parser core - when encountering text, process appropriately. */
static const char *parse_value(cJSON *item,const char *value,const char **ep)
{
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(item,value,ep); }
if (*value=='-' || (*value>='0' && *value<='9'))	{ return parse_number(item,value); }
if (*value=='[')				{ return parse_array(item,value,ep); }
if (*value=='{')				{ return parse_object(item,value,ep); }

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

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

/* Parse and print array */
/* Build an array from input text. */
static const char *parse_array(cJSON *item,const char *value,const char **ep)
{
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();
if (!item->child) return 0;		 /* memory fail */
value=skip(parse_value(child,skip(value),ep));	/* skip any spacing, get the value. */
if (!value) return 0;

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

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

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

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

if (p)
{
/* Compose the output array. */
i=p->offset;
ptr=ensure(p,1);if (!ptr) return 0;	*ptr='[';	p->offset++;
child=item->child;
while (child && !fail)
{
print_value(child,depth+1,fmt,p);
p->offset=update(p);
if (child->next) {len=fmt?2:1;ptr=ensure(p,len+1);if (!ptr) return 0;*ptr++=',';if(fmt)*ptr++=' ';*ptr=0;p->offset+=len;}
child=child->next;
}
ptr=ensure(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(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(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(len);
/* If that fails, we fail. */
if (!out) fail=1;

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

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

/* Parse and print object */
/* Build an object from the text. */
static const char *parse_object(cJSON *item,const char *value,const char **ep)
{
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();
if (!item->child) return 0;
value=skip(parse_string(child,skip(value),ep));
if (!value) return 0;
child->string=child->valuestring;child->valuestring=0;
if (*value!=':') {*ep=value;return 0;}	/* fail! */
value=skip(parse_value(child,skip(value+1),ep));	/* skip any spacing, get the value. */
if (!value) return 0;

while (*value==',')
{
cJSON *new_item;
if (!(new_item=cJSON_New_Item()))	return 0; /* memory fail */
child->next=new_item;new_item->prev=child;child=new_item;
value=skip(parse_string(child,skip(value+1),ep));
if (!value) return 0;
child->string=child->valuestring;child->valuestring=0;
if (*value!=':') {*ep=value;return 0;}	/* fail! */
value=skip(parse_value(child,skip(value+1),ep));	/* 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. */
static char *print_object(cJSON *item,int depth,int fmt,printbuffer *p)
{
char **entries=0,**names=0;
char *out=0,*ptr,*ret,*str;int len=7,i=0,j;
cJSON *child=item->child;
int numentries=0,fail=0;
size_t tmplen=0;
/* Count the number of entries. */
while (child) numentries++,child=child->next;
/* Explicitly handle empty object case */
if (!numentries)
{
if (p) out=ensure(p,fmt?depth+4:3);
else	out=(char*)cJSON_malloc(fmt?depth+4:3);
if (!out)	return 0;
ptr=out;*ptr++='{';
if (fmt) {*ptr++='\n';for (i=0;i<depth;i++) *ptr++='\t';}
*ptr++='}';*ptr++=0;
return out;
}
if (p)
{
/* Compose the output: */
i=p->offset;
len=fmt?2:1;	ptr=ensure(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(p,depth);	if (!ptr) return 0;
for (j=0;j<depth;j++) *ptr++='\t';
p->offset+=depth;
}
print_string_ptr(child->string,p);
p->offset=update(p);

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

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

len=(fmt?1:0)+(child->next?1:0);
ptr=ensure(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(p,fmt?(depth+1):2);	 if (!ptr) return 0;
if (fmt)	for (i=0;i<depth-1;i++) *ptr++='\t';
*ptr++='}';*ptr=0;
out=(p->buffer)+i;
}
else
{
/* Allocate space for the names and the objects */
entries=(char**)cJSON_malloc(numentries*sizeof(char*));
if (!entries) return 0;
names=(char**)cJSON_malloc(numentries*sizeof(char*));
if (!names) {cJSON_free(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 && !fail)
{
names[i]=str=print_string_ptr(child->string,0);
entries[i++]=ret=print_value(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(len);
if (!out) fail=1;

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

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

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

/* Wrapper for parse and print */
/* Parse an object - create a new root, and populate. */
cJSON *cJSON_ParseWithOpts(const char *value,const char **return_parse_end,int require_null_terminated)
{
const char *end=0,**ep=return_parse_end?return_parse_end:&global_ep;
cJSON *c=cJSON_New_Item();
*ep=0;
if (!c) return 0;       /* memory fail */

end=parse_value(c,skip(value),ep);
if (!end)	{cJSON_Delete(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(c);*ep=end;return 0;}}
if (return_parse_end) *return_parse_end=end;
return c;
}
/* Default options for cJSON_Parse */
cJSON *cJSON_Parse(const char *value) {return cJSON_ParseWithOpts(value,0,0);}

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

/* JSON utility functions */
/* 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?array->child:0;while (c && item>0) item--,c=c->next; return c;}
cJSON *cJSON_GetObjectItem(cJSON *object,const char *string)	{cJSON *c=object?object->child:0;while (c && cJSON_strcasecmp(c->string,string)) c=c->next; return c;}
int cJSON_HasObjectItem(cJSON *object,const char *string)		{return cJSON_GetObjectItem(object,string)?1:0;}

/* Utility for array list handling. */
static void suffix_object(cJSON *prev,cJSON *item) {prev->next=item;item->prev=prev;}
/* Utility for handling references. */
static cJSON *create_reference(cJSON *item) {cJSON *ref=cJSON_New_Item();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(cJSON *object,const char *string,cJSON *item)	{if (!item) return; if (item->string) cJSON_free(item->string);item->string=cJSON_strdup(string);cJSON_AddItemToArray(object,item);}
void   cJSON_AddItemToObjectCS(cJSON *object,const char *string,cJSON *item)	{if (!item) return; if (!(item->type&cJSON_StringIsConst) && item->string) cJSON_free(item->string);item->string=(char*)string;item->type|=cJSON_StringIsConst;cJSON_AddItemToArray(object,item);}
void	cJSON_AddItemReferenceToArray(cJSON *array, cJSON *item)						{cJSON_AddItemToArray(array,create_reference(item));}
void	cJSON_AddItemReferenceToObject(cJSON *object,const char *string,cJSON *item)	{cJSON_AddItemToObject(object,string,create_reference(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(cJSON *array,int which)			{cJSON_Delete(cJSON_DetachItemFromArray(array,which));}
cJSON *cJSON_DetachItemFromObject(cJSON *object,const char *string) {int i=0;cJSON *c=object->child;while (c && cJSON_strcasecmp(c->string,string)) i++,c=c->next;if (c) return cJSON_DetachItemFromArray(object,i);return 0;}
void   cJSON_DeleteItemFromObject(cJSON *object,const char *string) {cJSON_Delete(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(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(c);}
void   cJSON_ReplaceItemInObject(cJSON *object,const char *string,cJSON *newitem){int i=0;cJSON *c=object->child;while(c && cJSON_strcasecmp(c->string,string))i++,c=c->next;if(c){newitem->string=cJSON_strdup(string);cJSON_ReplaceItemInArray(object,i,newitem);}}

/* Create basic types: */
cJSON *cJSON_CreateNull(void)					{cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_NULL;return item;}
cJSON *cJSON_CreateTrue(void)					{cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_True;return item;}
cJSON *cJSON_CreateFalse(void)					{cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_False;return item;}
cJSON *cJSON_CreateBool(int b)					{cJSON *item=cJSON_New_Item();if(item)item->type=b?cJSON_True:cJSON_False;return item;}
cJSON *cJSON_CreateNumber(double num)			{cJSON *item=cJSON_New_Item();if(item){item->type=cJSON_Number;item->valuedouble=num;item->valueint=(int)num;}return item;}
cJSON *cJSON_CreateString(const char *string)	{cJSON *item=cJSON_New_Item();if(item){item->type=cJSON_String;item->valuestring=cJSON_strdup(string);if(!item->valuestring){cJSON_Delete(item);return 0;}}return item;}
cJSON *cJSON_CreateArray(void)					{cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_Array;return item;}
cJSON *cJSON_CreateObject(void)					{cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_Object;return item;}

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

/* Duplication */
cJSON *cJSON_Duplicate(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();
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(item->valuestring);	if (!newitem->valuestring)	{cJSON_Delete(newitem);return 0;}}
if (item->string)		{newitem->string=cJSON_strdup(item->string);			if (!newitem->string)		{cJSON_Delete(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(cptr,1);		/* Duplicate (with recurse) each item in the ->next chain */
if (!newchild) {cJSON_Delete(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. */
}

Reference