概述
C语言函数库写JSON文件 ：
从缓冲区中解析出JSON结构：extern cJSON *cJSON_Parse(const char *value);
解析一块JSON数据返回cJSON结构， 在使用完之后调用cJSON_Delete函数释放json对象结构。
将传入的JSON结构转化为字符串 ：extern char *cJSON_Print(cJSON *item);
可用于输出到输出设备， 使用完之后free(char *) 。
将JSON结构所占用的数据空间释放 ：void cJSON_Delete(cJSON *c)
创建一个值类型的数据 ：extern cJSON *cJSON_CreateNumber(double num);
extern cJSON *cJSON_CreateString(const char *string);
extern cJSON *cJSON_CreateArray(void);
创建一个对象（文档） ：extern cJSON *cJSON_CreateObject(void);
数组创建以及添加 ：cJSON *cJSON_CreateIntArray(const int *numbers,int count);
void cJSON_AddItemToArray(cJSON *array, cJSON *item);
JSON嵌套 ：
【 向对象中增加键值对】 cJSON_AddItemToObject(root, "rows", 值类型数据相关函数());
【 向对象中增加数组】 cJSON_AddItemToObject(root, "rows", cJSON_CreateArray());
【 向数组中增加对象】 cJSON_AddItemToArray(rows, cJSON_CreateObject());
几个能提高操作效率的宏函数 ：#define cJSON_AddNumberToObject(object,name,n)
cJSON_AddItemToObject(object, name,cJSON_CreateNumber(n))
#define cJSON_AddStringToObject(object,name,s)
cJSON_AddItemToObject(object, name, cJSON_CreateString(s))
C语言库函数解析JSON文件 ：
根据键找json结点 ：extern cJSON *cJSON_GetObjectItem(cJSON *object,const char *string)
判断是否有key是string的项 如果有返回1 否则返回0 ：extern int cJSON_HasObjectItem(cJSON *object,const char *string)
{ return cJSON_GetObjectItem(object,string)?1:0; }
返回数组结点array中成员的个数 ：extern int cJSON_GetArraySize(cJSON *array);
根据数组下标index取array数组结点的第index个成员 返回该成员节点 ：extern cJSON *cJSON_GetArrayItem(cJSON *array,int index);
遍历数组 ：#define cJSON_ArrayForEach(pos, head) for(pos = (head)->child; pos != NULL; pos = pos->next)
json构建：
cJSON * jsonHead = NULL;
cJSON * jsonListArray = NULL;
cJSON * jsonItem = NULL;
jsonHead = cJSON_CreateObject();
cJSON_AddItemToObject(jsonHead, JSON_CHAT_UI_MEMBER_TOTAL, cJSON_CreateNumber(member_total));
cJSON_AddItemToObject(jsonHead, JSON_CHAT_UI_USERID, cJSON_CreateNumber(pInfo->UserId));
//list
jsonListArray = cJSON_CreateArray();
for(i = 0; i < pInfo->member_total; i++)
{
jsonItem = cJSON_CreateObject();
cJSON_AddItemToObject(jsonItem, JSON_CHAT_UI_IMAGE_ID, cJSON_CreateNumber(ImageId));
cJSON_AddItemToArray(jsonListArray, jsonItem);
}
//add list to header node
cJSON_AddItemToObject(jsonHead, JSON_CHAT_UI_MEMBER_INFO, jsonListArray);
//get json data point
pListData = cJSON_Print(jsonHead);
//write to file
ret = FS_Write(fs_hdlr, pListData, dataLen, &write_size);
...
//free json data
if (NULL != jsonHead){
cJSON_Delete(jsonHead);
jsonHead = NULL;
}
if (NULL != pListData){
free(pListData);
pListData = NULL;
}
json解析：
cJSON * jsonHead = NULL;
cJSON * jsonListArray = NULL;
cJSON * jsonListItem = NULL;
cJSON * jsonObj = NULL;
U8 listTotalNum = 0;
//get list data
dataLen = get_file_data(localFileName, &pListData);
//parse header
jsonHead=cJSON_Parse(pListData);
jsonObj = cJSON_GetObjectItem(jsonHead, JSON_CHAT_UI_MEMBER_TOTAL);
pInfo->member_total = jsonObj->valueint;
//get list array json
jsonListArray = cJSON_GetObjectItem(jsonHead, JSON_CHAT_UI_MEMBER_INFO);
//parse list array json
listTotalNum = cJSON_GetArraySize(jsonListArray);
for(i = 0 ; i < listTotalNum ; i++)
{
jsonListItem=cJSON_GetArrayItem(jsonListArray, i);
if(NULL != jsonListItem)
{
jsonObj = cJSON_GetObjectItem(jsonListItem, JSON_CHAT_UI_IMAGE_ID);
if(jsonObj)
pInfo->member_list[i].ImageId= jsonObj->valueint;
...
}
}
//free json data
if (NULL != jsonHead){
cJSON_Delete(jsonHead);
jsonHead = NULL;
}
保存的文件结果：
{
"member_total": 36,
"UserId": 352618,
"InfoArray": [{
"ImageId": 0
}, {
"ImageId": 0
}, {
"ImageId": 0
}, {
"ImageId": 0
}, {
"ImageId": 0
}, {
"ImageId": 0
}]
}
cJSON.h
#ifndef cJSON__h
#define cJSON__h
#ifdef __cplusplus
extern "C"
{
#endif
/* cJSON Types: */
#define cJSON_False 0
#define cJSON_True 1
#define cJSON_NULL 2
#define cJSON_Number 3
#define cJSON_String 4
#define cJSON_Array 5
#define cJSON_Object 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;
typedef struct cJSON_Hooks {
void *(*malloc_fn)(size_t sz);
void (*free_fn)(void *ptr);
} cJSON_Hooks;
/* Supply malloc, realloc and free functions to cJSON */
extern void cJSON_InitHooks(cJSON_Hooks* hooks);
/* Supply a block of JSON, and this returns a cJSON object you can interrogate. Call cJSON_Delete when finished. */
extern cJSON *cJSON_Parse(const char *value);
/* Render a cJSON entity to text for transfer/storage. Free the char* when finished. */
extern char *cJSON_Print(cJSON *item);
/* Render a cJSON entity to text for transfer/storage without any formatting. Free the char* when finished. */
extern char *cJSON_PrintUnformatted(cJSON *item);
/* Render a cJSON entity to text using a buffered strategy. prebuffer is a guess at the final size. guessing well reduces reallocation. fmt=0 gives unformatted, =1 gives formatted */
extern char *cJSON_PrintBuffered(cJSON *item,int prebuffer,int fmt);
/* Delete a cJSON entity and all subentities. */
extern void cJSON_Delete(cJSON *c);
/* Returns the number of items in an array (or object). */
extern int cJSON_GetArraySize(cJSON *array);
/* Retrieve item number "item" from array "array". Returns NULL if unsuccessful. */
extern cJSON *cJSON_GetArrayItem(cJSON *array,int item);
/* Get item "string" from object. Case insensitive. */
extern cJSON *cJSON_GetObjectItem(cJSON *object,const char *string);
/* For analysing failed parses. This returns a pointer to the parse error. You'll probably need to look a few chars back to make sense of it. Defined when cJSON_Parse() returns 0. 0 when cJSON_Parse() succeeds. */
extern const char *cJSON_GetErrorPtr(void);
/* These calls create a cJSON item of the appropriate type. */
extern cJSON *cJSON_CreateNull(void);
extern cJSON *cJSON_CreateTrue(void);
extern cJSON *cJSON_CreateFalse(void);
extern cJSON *cJSON_CreateBool(int b);
extern cJSON *cJSON_CreateNumber(double num);
extern cJSON *cJSON_CreateString(const char *string);
extern cJSON *cJSON_CreateArray(void);
extern cJSON *cJSON_CreateObject(void);
/* These utilities create an Array of count items. */
extern cJSON *cJSON_CreateIntArray(const int *numbers,int count);
extern cJSON *cJSON_CreateFloatArray(const float *numbers,int count);
extern cJSON *cJSON_CreateDoubleArray(const double *numbers,int count);
extern cJSON *cJSON_CreateStringArray(const char **strings,int count);
/* Append item to the specified array/object. */
extern void cJSON_AddItemToArray(cJSON *array, cJSON *item);
extern void cJSON_AddItemToObject(cJSON *object,const char *string,cJSON *item);
extern void cJSON_AddItemToObjectCS(cJSON *object,const char *string,cJSON *item); /* Use this when string is definitely const (i.e. a literal, or as good as), and will definitely survive the cJSON object */
/* Append reference to item to the specified array/object. Use this when you want to add an existing cJSON to a new cJSON, but don't want to corrupt your existing cJSON. */
extern void cJSON_AddItemReferenceToArray(cJSON *array, cJSON *item);
extern void cJSON_AddItemReferenceToObject(cJSON *object,const char *string,cJSON *item);
/* Remove/Detatch items from Arrays/Objects. */
extern cJSON *cJSON_DetachItemFromArray(cJSON *array,int which);
extern void cJSON_DeleteItemFromArray(cJSON *array,int which);
extern cJSON *cJSON_DetachItemFromObject(cJSON *object,const char *string);
extern void cJSON_DeleteItemFromObject(cJSON *object,const char *string);
/* Update array items. */
extern void cJSON_InsertItemInArray(cJSON *array,int which,cJSON *newitem); /* Shifts pre-existing items to the right. */
extern void cJSON_ReplaceItemInArray(cJSON *array,int which,cJSON *newitem);
extern void cJSON_ReplaceItemInObject(cJSON *object,const char *string,cJSON *newitem);
/* Duplicate a cJSON item */
extern cJSON *cJSON_Duplicate(cJSON *item,int recurse);
/* Duplicate will create a new, identical cJSON item to the one you pass, in new memory that will
need to be released. With recurse!=0, it will duplicate any children connected to the item.
The item->next and ->prev pointers are always zero on return from Duplicate. */
/* ParseWithOpts allows you to require (and check) that the JSON is null terminated, and to retrieve the pointer to the final byte parsed. */
extern cJSON *cJSON_ParseWithOpts(const char *value,const char **return_parse_end,int require_null_terminated);
extern void cJSON_Minify(char *json);
/* Macros for creating things quickly. */
#define cJSON_AddNullToObject(object,name) cJSON_AddItemToObject(object, name, cJSON_CreateNull())
#define cJSON_AddTrueToObject(object,name) cJSON_AddItemToObject(object, name, cJSON_CreateTrue())
#define cJSON_AddFalseToObject(object,name) cJSON_AddItemToObject(object, name, cJSON_CreateFalse())
#define cJSON_AddBoolToObject(object,name,b) cJSON_AddItemToObject(object, name, cJSON_CreateBool(b))
#define cJSON_AddNumberToObject(object,name,n) cJSON_AddItemToObject(object, name, cJSON_CreateNumber(n))
#define cJSON_AddStringToObject(object,name,s) cJSON_AddItemToObject(object, name, cJSON_CreateString(s))
/* When assigning an integer value, it needs to be propagated to valuedouble too. */
#define cJSON_SetIntValue(object,val) ((object)?(object)->valueint=(object)->valuedouble=(val):(val))
#define cJSON_SetNumberValue(object,val) ((object)?(object)->valueint=(object)->valuedouble=(val):(val))
#ifdef __cplusplus
}
#endif
#endif
cJON.c
/* cJSON */
/* JSON parser in C. */
#include <string.h>
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <float.h>
#include <limits.h>
#include <ctype.h>
#include "cJSON.h"
#include "CSInteract.h"
static const char *ep;
typedef struct {char *buffer; int length; int offset; } printbuffer;
static void *(*cJSON_malloc)(size_t sz) = malloc;
static void (*cJSON_free)(void *ptr) = free;
const char *cJSON_GetErrorPtr(void) {return ep;}
/* Predeclare these prototypes. */
static const char *parse_value(cJSON *item,const char *value);
static char *print_value(cJSON *item,int depth,int fmt,printbuffer *p);
static const char *parse_array(cJSON *item,const char *value);
static char *print_array(cJSON *item,int depth,int fmt,printbuffer *p);
static const char *parse_object(cJSON *item,const char *value);
static char *print_object(cJSON *item,int depth,int fmt,printbuffer *p);
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;
}
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;
}
}
/* 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;
}
static int pow2gt (int x)
{
--x;
x|=x>>1;
x|=x>>2;
x|=x>>4;
x|=x>>8;
x|=x>>16;
return x+1;
}
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);
}
/* 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 (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;
}
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;
}
/* 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 *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(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;
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++;
item->valuestring=out;
item->type=cJSON_String;
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;
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;
}
if (!str)
{
if (p) out=ensure(p,3);
else out=(char*)cJSON_malloc(3);
if (!out) return 0;
strcpy(out,"""");
return out;
}
ptr=str;while ((token=*ptr) && ++len) {if (strchr(""\bfnrt",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);
}
/* 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 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;
cJSON *c=cJSON_New_Item();
ep=0;
if (!c) return 0; /* memory fail */
end=parse_value(c,skip(value));
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);
}
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);
return p.buffer;
}
/* Parser core - when encountering text, process appropriately. */
static const char *parse_value(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(item,value); }
if (*value=='-' || (*value>='0' && *value<='9')) { return parse_number(item,value); }
if (*value=='[') { return parse_array(item,value); }
if (*value=='{') { return parse_object(item,value); }
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;
}
/* Build an array from input text. */
static const char *parse_array(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();
if (!item->child) return 0; /* memory fail */
value=skip(parse_value(child,skip(value))); /* 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)));
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;
}
/* Build an object from the text. */
static const char *parse_object(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();
if (!item->child) return 0;
value=skip(parse_string(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(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())) return 0; /* memory fail */
child->next=new_item;new_item->prev=child;child=new_item;
value=skip(parse_string(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(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. */
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-1;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)
{
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;
}
/* 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 && cJSON_strcasecmp(c->string,string))
c=c->next;
return c;
}
/* 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) {
/* list is empty, start new one */
array->child = item;
array->child->prev = item;
}
else {
/* append to the end */
if (array->child->prev) {
item->prev = array->child->prev;
array->child->prev->next = item;
array->child->prev = item;
item->next = NULL;
}
else {
while (c->next)
c = c->next;
suffix_object(c, item);
array->child->prev = 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);}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(!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(!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(!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(!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. */
}
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