JsonParser in C with json-c Library | json_object_object_get(…) not declared
I am new here and try to implement a Json Parser.
I find a Tutorial (https://linuxprograms.wordpress.com/2010/05/20/json-c-libjson-tutorial/) for a Json Parser Programm.
So i have a Json-File Input like this one:
{ "DefaultTest": "SS",
"Send": {
"ip_hl": 4,
"ip_v": 4,
....
}
}
I use the Code in the Tutorial (https://linuxprograms.wordpress.com/2010/08/19/json_parser_json-c/) and try to understand this one. But i get an Error, that the Method json_object_object_get_get(jobj, key) is not declared
.
So find a Wibesite (https://json-c.github.io/json-c/json-c-0.10/doc/html/deprecated.html) with Deprecated List in there for the json-lib. In this there is stay that i should use json_object_object_get_ex
.
If I use the method i get this warning: assignment makes pointer from integer without a cast [-Wint-conversion] jobj = json_object_object_get_ex(jobj, key, NULL);
What is this mean? How can I fix it?
My Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <json/json.h>
void json_parse(json_object * jobj) {
enum json_type type;
json_object_object_foreach(jobj, key, val)
{
printf("type: %dn", type);
type = json_object_get_type(val);
switch (type) {
case json_type_boolean:
case json_type_double:
case json_type_int:
case json_type_string:
// print_json_value(val);
break;
case json_type_object:
printf("json_type_objectn");
// jobj = json_object_object_get(jobj, key);
jobj = json_object_object_get_ex(jobj, key, NULL);
json_parse(jobj);
break;
case json_type_array:
// printf("json_type_arrayn");
// json_parse_array(jobj,key);
break;
}
}
}
int main() {
char *path = "../Paketspezifikationen/Default-File/DefaultConfig2.json";
FILE *fp;
char *data = NULL;
if ((fp = fopen(path, "rb")) == NULL) {
} else if (fseek(fp, 0, SEEK_END) != 0) {
fclose(fp);
} else {
long size = ftell(fp);
if (size > 0 && (data = (char *) malloc(size + 1)) != NULL) {
fseek(fp, 0, SEEK_SET);
if (fread(data, 1, size, fp) != (size_t) size) {
free(data);
data = NULL;
} else {
data[size] = '';
}
}
fclose(fp);
}
printf("JSON string: %sn", data); // return data
json_object * jobj = json_tokener_parse(data);
json_parse(jobj);
}
In Main I read first the Json File and store it in a String and try to get all my keys and values from there. So i use the json parser.
Hope that you can help me.
c json json-lib
add a comment |
I am new here and try to implement a Json Parser.
I find a Tutorial (https://linuxprograms.wordpress.com/2010/05/20/json-c-libjson-tutorial/) for a Json Parser Programm.
So i have a Json-File Input like this one:
{ "DefaultTest": "SS",
"Send": {
"ip_hl": 4,
"ip_v": 4,
....
}
}
I use the Code in the Tutorial (https://linuxprograms.wordpress.com/2010/08/19/json_parser_json-c/) and try to understand this one. But i get an Error, that the Method json_object_object_get_get(jobj, key) is not declared
.
So find a Wibesite (https://json-c.github.io/json-c/json-c-0.10/doc/html/deprecated.html) with Deprecated List in there for the json-lib. In this there is stay that i should use json_object_object_get_ex
.
If I use the method i get this warning: assignment makes pointer from integer without a cast [-Wint-conversion] jobj = json_object_object_get_ex(jobj, key, NULL);
What is this mean? How can I fix it?
My Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <json/json.h>
void json_parse(json_object * jobj) {
enum json_type type;
json_object_object_foreach(jobj, key, val)
{
printf("type: %dn", type);
type = json_object_get_type(val);
switch (type) {
case json_type_boolean:
case json_type_double:
case json_type_int:
case json_type_string:
// print_json_value(val);
break;
case json_type_object:
printf("json_type_objectn");
// jobj = json_object_object_get(jobj, key);
jobj = json_object_object_get_ex(jobj, key, NULL);
json_parse(jobj);
break;
case json_type_array:
// printf("json_type_arrayn");
// json_parse_array(jobj,key);
break;
}
}
}
int main() {
char *path = "../Paketspezifikationen/Default-File/DefaultConfig2.json";
FILE *fp;
char *data = NULL;
if ((fp = fopen(path, "rb")) == NULL) {
} else if (fseek(fp, 0, SEEK_END) != 0) {
fclose(fp);
} else {
long size = ftell(fp);
if (size > 0 && (data = (char *) malloc(size + 1)) != NULL) {
fseek(fp, 0, SEEK_SET);
if (fread(data, 1, size, fp) != (size_t) size) {
free(data);
data = NULL;
} else {
data[size] = '';
}
}
fclose(fp);
}
printf("JSON string: %sn", data); // return data
json_object * jobj = json_tokener_parse(data);
json_parse(jobj);
}
In Main I read first the Json File and store it in a String and try to get all my keys and values from there. So i use the json parser.
Hope that you can help me.
c json json-lib
Neither the tutorial, nor your code containsjson_object_object_get_get
. Please copy&paste the exact message. You do not show us a definition forkey
.
– Gerhardh
Nov 19 '18 at 14:49
add a comment |
I am new here and try to implement a Json Parser.
I find a Tutorial (https://linuxprograms.wordpress.com/2010/05/20/json-c-libjson-tutorial/) for a Json Parser Programm.
So i have a Json-File Input like this one:
{ "DefaultTest": "SS",
"Send": {
"ip_hl": 4,
"ip_v": 4,
....
}
}
I use the Code in the Tutorial (https://linuxprograms.wordpress.com/2010/08/19/json_parser_json-c/) and try to understand this one. But i get an Error, that the Method json_object_object_get_get(jobj, key) is not declared
.
So find a Wibesite (https://json-c.github.io/json-c/json-c-0.10/doc/html/deprecated.html) with Deprecated List in there for the json-lib. In this there is stay that i should use json_object_object_get_ex
.
If I use the method i get this warning: assignment makes pointer from integer without a cast [-Wint-conversion] jobj = json_object_object_get_ex(jobj, key, NULL);
What is this mean? How can I fix it?
My Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <json/json.h>
void json_parse(json_object * jobj) {
enum json_type type;
json_object_object_foreach(jobj, key, val)
{
printf("type: %dn", type);
type = json_object_get_type(val);
switch (type) {
case json_type_boolean:
case json_type_double:
case json_type_int:
case json_type_string:
// print_json_value(val);
break;
case json_type_object:
printf("json_type_objectn");
// jobj = json_object_object_get(jobj, key);
jobj = json_object_object_get_ex(jobj, key, NULL);
json_parse(jobj);
break;
case json_type_array:
// printf("json_type_arrayn");
// json_parse_array(jobj,key);
break;
}
}
}
int main() {
char *path = "../Paketspezifikationen/Default-File/DefaultConfig2.json";
FILE *fp;
char *data = NULL;
if ((fp = fopen(path, "rb")) == NULL) {
} else if (fseek(fp, 0, SEEK_END) != 0) {
fclose(fp);
} else {
long size = ftell(fp);
if (size > 0 && (data = (char *) malloc(size + 1)) != NULL) {
fseek(fp, 0, SEEK_SET);
if (fread(data, 1, size, fp) != (size_t) size) {
free(data);
data = NULL;
} else {
data[size] = '';
}
}
fclose(fp);
}
printf("JSON string: %sn", data); // return data
json_object * jobj = json_tokener_parse(data);
json_parse(jobj);
}
In Main I read first the Json File and store it in a String and try to get all my keys and values from there. So i use the json parser.
Hope that you can help me.
c json json-lib
I am new here and try to implement a Json Parser.
I find a Tutorial (https://linuxprograms.wordpress.com/2010/05/20/json-c-libjson-tutorial/) for a Json Parser Programm.
So i have a Json-File Input like this one:
{ "DefaultTest": "SS",
"Send": {
"ip_hl": 4,
"ip_v": 4,
....
}
}
I use the Code in the Tutorial (https://linuxprograms.wordpress.com/2010/08/19/json_parser_json-c/) and try to understand this one. But i get an Error, that the Method json_object_object_get_get(jobj, key) is not declared
.
So find a Wibesite (https://json-c.github.io/json-c/json-c-0.10/doc/html/deprecated.html) with Deprecated List in there for the json-lib. In this there is stay that i should use json_object_object_get_ex
.
If I use the method i get this warning: assignment makes pointer from integer without a cast [-Wint-conversion] jobj = json_object_object_get_ex(jobj, key, NULL);
What is this mean? How can I fix it?
My Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <json/json.h>
void json_parse(json_object * jobj) {
enum json_type type;
json_object_object_foreach(jobj, key, val)
{
printf("type: %dn", type);
type = json_object_get_type(val);
switch (type) {
case json_type_boolean:
case json_type_double:
case json_type_int:
case json_type_string:
// print_json_value(val);
break;
case json_type_object:
printf("json_type_objectn");
// jobj = json_object_object_get(jobj, key);
jobj = json_object_object_get_ex(jobj, key, NULL);
json_parse(jobj);
break;
case json_type_array:
// printf("json_type_arrayn");
// json_parse_array(jobj,key);
break;
}
}
}
int main() {
char *path = "../Paketspezifikationen/Default-File/DefaultConfig2.json";
FILE *fp;
char *data = NULL;
if ((fp = fopen(path, "rb")) == NULL) {
} else if (fseek(fp, 0, SEEK_END) != 0) {
fclose(fp);
} else {
long size = ftell(fp);
if (size > 0 && (data = (char *) malloc(size + 1)) != NULL) {
fseek(fp, 0, SEEK_SET);
if (fread(data, 1, size, fp) != (size_t) size) {
free(data);
data = NULL;
} else {
data[size] = '';
}
}
fclose(fp);
}
printf("JSON string: %sn", data); // return data
json_object * jobj = json_tokener_parse(data);
json_parse(jobj);
}
In Main I read first the Json File and store it in a String and try to get all my keys and values from there. So i use the json parser.
Hope that you can help me.
c json json-lib
c json json-lib
asked Nov 19 '18 at 12:36
SebastianSebastian
14
14
Neither the tutorial, nor your code containsjson_object_object_get_get
. Please copy&paste the exact message. You do not show us a definition forkey
.
– Gerhardh
Nov 19 '18 at 14:49
add a comment |
Neither the tutorial, nor your code containsjson_object_object_get_get
. Please copy&paste the exact message. You do not show us a definition forkey
.
– Gerhardh
Nov 19 '18 at 14:49
Neither the tutorial, nor your code contains
json_object_object_get_get
. Please copy&paste the exact message. You do not show us a definition for key
.– Gerhardh
Nov 19 '18 at 14:49
Neither the tutorial, nor your code contains
json_object_object_get_get
. Please copy&paste the exact message. You do not show us a definition for key
.– Gerhardh
Nov 19 '18 at 14:49
add a comment |
1 Answer
1
active
oldest
votes
The json_object_object_get_ex()
function returns a json_bool
(which is actually an int
) indicating whether the given key is found in the parent JSON object, so you can't assign the function return value to jobj
, which is a pointer: that's where the warning comes from.
Since in your code you already have a pointer (in the val
variable) to the JSON object corresponding to a given key, you can achieve what you want more simply by avoiding the call to json_object_object_get_ex()
and calling json_parse(val)
.
thank it helps ^^. I try to fix it on my own first. So i have use the 'json_object_object_get_ex(jobj, key, &tmp);' and parse it in a jobj ('jobj = json_tokener_parse(json_object_to_json_string(tmp));') after that i use my 'json_parse(jobj) to parse the obj. I could start the Programm and it hat the impression that it works. Properly, after i test the Programm other problems came. With your solution I was able to fix these problems thank you.
– Sebastian
Nov 20 '18 at 13:29
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
The json_object_object_get_ex()
function returns a json_bool
(which is actually an int
) indicating whether the given key is found in the parent JSON object, so you can't assign the function return value to jobj
, which is a pointer: that's where the warning comes from.
Since in your code you already have a pointer (in the val
variable) to the JSON object corresponding to a given key, you can achieve what you want more simply by avoiding the call to json_object_object_get_ex()
and calling json_parse(val)
.
thank it helps ^^. I try to fix it on my own first. So i have use the 'json_object_object_get_ex(jobj, key, &tmp);' and parse it in a jobj ('jobj = json_tokener_parse(json_object_to_json_string(tmp));') after that i use my 'json_parse(jobj) to parse the obj. I could start the Programm and it hat the impression that it works. Properly, after i test the Programm other problems came. With your solution I was able to fix these problems thank you.
– Sebastian
Nov 20 '18 at 13:29
add a comment |
The json_object_object_get_ex()
function returns a json_bool
(which is actually an int
) indicating whether the given key is found in the parent JSON object, so you can't assign the function return value to jobj
, which is a pointer: that's where the warning comes from.
Since in your code you already have a pointer (in the val
variable) to the JSON object corresponding to a given key, you can achieve what you want more simply by avoiding the call to json_object_object_get_ex()
and calling json_parse(val)
.
thank it helps ^^. I try to fix it on my own first. So i have use the 'json_object_object_get_ex(jobj, key, &tmp);' and parse it in a jobj ('jobj = json_tokener_parse(json_object_to_json_string(tmp));') after that i use my 'json_parse(jobj) to parse the obj. I could start the Programm and it hat the impression that it works. Properly, after i test the Programm other problems came. With your solution I was able to fix these problems thank you.
– Sebastian
Nov 20 '18 at 13:29
add a comment |
The json_object_object_get_ex()
function returns a json_bool
(which is actually an int
) indicating whether the given key is found in the parent JSON object, so you can't assign the function return value to jobj
, which is a pointer: that's where the warning comes from.
Since in your code you already have a pointer (in the val
variable) to the JSON object corresponding to a given key, you can achieve what you want more simply by avoiding the call to json_object_object_get_ex()
and calling json_parse(val)
.
The json_object_object_get_ex()
function returns a json_bool
(which is actually an int
) indicating whether the given key is found in the parent JSON object, so you can't assign the function return value to jobj
, which is a pointer: that's where the warning comes from.
Since in your code you already have a pointer (in the val
variable) to the JSON object corresponding to a given key, you can achieve what you want more simply by avoiding the call to json_object_object_get_ex()
and calling json_parse(val)
.
answered Nov 19 '18 at 17:07
Francesco LavraFrancesco Lavra
21317
21317
thank it helps ^^. I try to fix it on my own first. So i have use the 'json_object_object_get_ex(jobj, key, &tmp);' and parse it in a jobj ('jobj = json_tokener_parse(json_object_to_json_string(tmp));') after that i use my 'json_parse(jobj) to parse the obj. I could start the Programm and it hat the impression that it works. Properly, after i test the Programm other problems came. With your solution I was able to fix these problems thank you.
– Sebastian
Nov 20 '18 at 13:29
add a comment |
thank it helps ^^. I try to fix it on my own first. So i have use the 'json_object_object_get_ex(jobj, key, &tmp);' and parse it in a jobj ('jobj = json_tokener_parse(json_object_to_json_string(tmp));') after that i use my 'json_parse(jobj) to parse the obj. I could start the Programm and it hat the impression that it works. Properly, after i test the Programm other problems came. With your solution I was able to fix these problems thank you.
– Sebastian
Nov 20 '18 at 13:29
thank it helps ^^. I try to fix it on my own first. So i have use the 'json_object_object_get_ex(jobj, key, &tmp);' and parse it in a jobj ('jobj = json_tokener_parse(json_object_to_json_string(tmp));') after that i use my 'json_parse(jobj) to parse the obj. I could start the Programm and it hat the impression that it works. Properly, after i test the Programm other problems came. With your solution I was able to fix these problems thank you.
– Sebastian
Nov 20 '18 at 13:29
thank it helps ^^. I try to fix it on my own first. So i have use the 'json_object_object_get_ex(jobj, key, &tmp);' and parse it in a jobj ('jobj = json_tokener_parse(json_object_to_json_string(tmp));') after that i use my 'json_parse(jobj) to parse the obj. I could start the Programm and it hat the impression that it works. Properly, after i test the Programm other problems came. With your solution I was able to fix these problems thank you.
– Sebastian
Nov 20 '18 at 13:29
add a comment |
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Neither the tutorial, nor your code contains
json_object_object_get_get
. Please copy&paste the exact message. You do not show us a definition forkey
.– Gerhardh
Nov 19 '18 at 14:49