Thread: free problem with struct

hi i have a problem when i use free with a structure inside a structure ...this is the code...

Code:

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

typedef struct
{
	char *table_name;
	int id_client[10];
} TABLE;

typedef struct
{
	char *db_name;
	TABLE *db_table;
} DB_RESOURCE;


int main(int argc, char **argv)
{
	DB_RESOURCE *db_list;



	char dbname[] = "database1";
	char dbtable[] = "table1";




	db_list = (DB_RESOURCE *)malloc(sizeof(DB_RESOURCE)); // te lo dichiara di 1

	db_list[0].db_name = (char *) malloc(sizeof(dbname));

	db_list[0].db_table = (TABLE *) malloc(sizeof(TABLE));



	db_list[0].db_table[0].table_name = (char *) malloc(sizeof(dbtable));


	strcpy(db_list[0].db_name, "database1");

	strcpy(db_list[0].db_table[0].table_name, "table1");


	db_list[0].db_table[0].id_client[0] = 28;





	printf("\n%s\n", db_list[0].db_name);

	printf("\n%s\n", db_list[0].db_table[0].table_name);


	printf("\n%ld\n", db_list->db_table->id_client[0]);




	free(db_list[0].db_name);

	free(db_list[0].db_table[0].table_name);



	free(db_list->db_table->id_client);
	

	printf("\n**** before the free ****\n");


	printf("\n%s\n", db_list[0].db_name);

	printf("\n%s\n", db_list[0].db_table[0].table_name);


	printf("\n%ld\n", db_list[0].db_table[0].id_client[0]);


	return 0;
}

and when i execute the program the latest free() does'nt have effect in fact the output is :

database1

table1

28

**** dopo la free ****

database1

hó@

28


help please....i don't know because i have this problem.....


Please use [code][/code]Tags

Code:

 int id_client[10];
....
 free(db_list->db_table->id_client);

The free function deallocates a memory block (memblock) that was previously allocated by a call to calloc, malloc, or realloc.
So your code is wrong.

so in this way the code is right???

free(db_list[0].db_table[0].id_client);

free(db_list[0].db_table[0].table_name);

free(db_list[0].db_name);

thx anyway....

but i want to free id_client...

what i have to do ???

but in this way i lost also char *table_name and i don't want to lost this information.... i want only to free data of id_client not of all struct TABLE......

i tried also in this way ubt the result is always the same...and i don't know how...
by me the problem is that there is a struct inside a struct and (i don't know for which problem) there is some problem...

plz help me ...

this is the code:

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#define FD_SET_SIZE 11

typedef struct
{
char *table_name;
int *id_client;
} TABLE;

typedef struct
{
char *db_name;
TABLE *db_table;
} DB_RESOURCE;

DB_RESOURCE* newEntry (char dbname[], char tablename[], int id);


int main(int argc, char **argv)
{
DB_RESOURCE *db_list;



char dbname[] = "database1";
char dbtable[] = "table1";

db_list = newEntry(dbname, dbtable, 28);


printf("\n%s\n", db_list[0].db_name);

printf("\n%s\n", db_list[0].db_table[0].table_name);

// printf("\n%ld\n", db_list[0].cazzo[0]);

printf("\n%ld\n", db_list[0].db_table[0].id_client[0]);




free(db_list[0].db_table[0].id_client);//error is here
free(db_list[0].db_table[0].table_name);
free(db_list[0].db_name);
//You should also include this
//free(db_list->db_table);




printf("\n**** after the free ****\n");


printf("\n%s\n", db_list[0].db_name);

printf("\n%s\n", db_list[0].db_table[0].table_name);


printf("\n%ld\n", db_list[0].db_table[0].id_client[0]);





return 0;
}


DB_RESOURCE* newEntry (char dbname[], char tablename[], int id)
{

DB_RESOURCE *db_list;

db_list = (DB_RESOURCE *)malloc(sizeof(DB_RESOURCE)); // te lo dichiara di 1

db_list[0].db_name = (char *) malloc(sizeof(dbname));

db_list[0].db_table = (TABLE *) malloc(sizeof(TABLE));

db_list[0].db_table[0].table_name = (char *) malloc(sizeof(tablename));

db_list[0].db_table[0].id_client[0] = (int) malloc( 10 * sizeof(int));

db_list[0].db_table[0].id_client[0] = id;



strcpy(db_list[0].db_name, dbname);

strcpy(db_list[0].db_table[0].table_name, tablename);

db_list[0].db_table[0].id_client[0] = id;


return db_list;
}

i've just added a function that do the mallocand the assignments...

thx...