Problems with editing and showing customer data - c - c

Question

I'm doing a customer and product management project in C. And right now I'm having some problems:
in the part of showing the customer's data, he doesn't show the whole name, only the first letter; the phone number puts a number that I didn't enter; in nif does not say what corresponds; as well as the email that put characters that I did not indicate.
Already in the edit part, it edits but not correctly, because it changes data that I didn't ask for and others I don't sample.
Stays like this:
-- customer creation:
enter image description here
-- show customer data:
enter image description here
This is my code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define BUFFER 64
/* List structure declared to store our data. */
typedef struct list {
int *customer_code;
char name;
int age;
int tin;
char email;
double phone;
char country;
struct list *next;
} Data;
/* Prototype of data handling functions. */
int *data_start(int *customer_code, char name, int age, int tin, char email, double phone, char country);
int *insert_data(Data *data, int *customer_code, char name, int age, int tin, char email, double phone, char country);
int *edita_dados(Dados *dados, int item, int *customer_code, char name, int age, int tin, char email, double phone, char country);
void display_data(Data *data);
void data_search(Data *data, char *key);
int *delete_data(Data *data);
int check_empty(Data *data);
/* Prototype of menu functions.*/
void insert(void);
void edit(void);
void displays(void);
void search(void);
void delete(void);
/* Initializes the main data structure. */
int *main = NULL;
/* Cria a nova lista apontando o proximo no para NULL. */
int *data_start(int *cliente_codigo, char name, int age, int tin, char email, double phone, char country) {
Data *new;
new = (Data *) malloc(sizeof (Data));
new->customer_code = (int *) malloc(strlen(customer_code) + 1);
strncpy(new->customer_code, customer_code, strlen(customer_code) + 1);
new->name = name;
new->age = age;
new->tin = tin;
new->email = email;
new->phone = phone;
new->country = country
new->next = NULL;
return new;
}
/* As the list is no longer empty, we point the next node to the previous list. */
int *insert_data(Data *data, int *customer_code, char name, int age, int tin, char email, double phone, char country) {
Data *new;
new = (Data *) malloc(sizeof (Data));
new->customer_code = (int *) malloc(strlen(customer_code) + 1);
strncpy(new->customer_code, customer_code, strlen(customer_code) + 1);
new->name = name;
new->age = age;
new->tin = tin;
new->email = email;
new->phone = phone;
new->country = country
new->next = Data;
return new;
}
/* Cycles through all fields in the list and prints until the next pointer reaches NULL. */
int *edita_dados(Data *data, int item, int *customer_code, char name, int age, int tin, char email, double phone, char country) {
int i = 0;
/*while(data != NULL && i <= item) {
data = data->next;
}*/
while (data->next != NULL && i < item) {
data = data->next;
++i;
}
if (data != NULL && i == item) {
strcpy(data->customer_code, customer_code);
new->name = name;
data->age = age;
data->tin = tin;
data->email = email;
data->phone = phone;
data->country = country
}
printf("Successfully edited.\n");
}
/* Cycles through all fields in the list and prints until the next pointer reaches NULL. */
void display_data(Data *data) {
printf("Registration Report\n\n");
printf("------------------------\n");
for (; data != NULL; data = data->next) {
printf("Name: %c\n", data->name);
printf("Age: %d\n", data->age);
printf("TIN: %d\n", data->tin);
printf("Email: %c\n", data->email);
printf("Phone: %lf\n", data->phone);
printf("Country: %c\n", data->country);
printf("------------------------\n");
}
}
/* Cycle through each end comparing the name to the key. */
void data_search(Data *data, char *key) {
int find = 0;
printf("registration data\n\n");
for (; data != NULL; data = data->next) {
if (strcmp(key, data->customer_code) == 0) {
printf("------------------------\n");
printf("Name: %c\n", data->name);
printf("Age: %d\n", data->age);
printf("TIN: %d\n", data->tin);
printf("Email: %c\n", data->email);
printf("Phone: %lf\n", data->phone);
printf("Country: %c\n", data->country);
printf("------------------------\n");
find++;
}
}
if (find == 0)
printf("No results found.\n\nPress a key to continue.\n\n");
else
printf("%d records were found.\n\nPress a key to continue.\n\n", find);
}
/* Deletes the last record entered. */
int *delete_data(Data *data) {
Data *new;
new = data->next;
free(data->customer_code);
free(data);
printf("The last record entered was deleted successfully!\n");
return new;
}
/* it's worth checking whether the list is NULL or not. */
int check_empty(Data *data) {
if (data == NULL) {
printf("List empty!\n");
return 1;
} else
return 0;
}
/* Gets the necessary data to call the data handling functions. */
void insert(void) {
int intend_tin;
Data d;
d.customer_code = (char *) malloc(BUFFER);
printf("Client Code: ");
scanf("%d", d.customer_code);
printf("Type your name: ");
scanf("%s", &d.name);
printf("\nEnter your age:");
scanf("%d", &d.age);
printf("\nEnter your email:");
scanf("%s", &d.email);
printf("\nEnter your mobile number: ");
scanf("%lf", &d.phone);
printf("TIN present? ");
scanf("%s", &intend_tin);
if (intend_tin == 's' || intend_tin == 'S') {
while (1) {
printf("\n\tEnter your TIN: ");
scanf("%d", &d.tin);
if (&d.tin >= 999999999) {
printf("\tNumber with more than 9 digits is not allowed. "
"Please try again.");
} else if (&d.tin <= 99999999) {
printf("\tNumber with less than 9 digits is not allowed. "
"Please try again.");
} else
break;
}
printf("\tValid.\n");
} else {
printf("TIN not entered\n");
}
printf("What is your country? ");
scanf("%s", &d.country);
if (main == NULL)
main = data_start(d.customer_code, d.name, d.age, d.email, d.phone, d.tin, d.country);
else
main = insert_data(main, d.customer_code, d.name, d.age, d.email, d.phone, d.tin, d.country);
}
/* Gets the necessary data to call the data handling functions. */
void edit(void) {
int item = 0;
Data d;
d.customer_code = (char *) malloc(BUFFER);
printf("Enter the customer code you want to change the data:");
scanf("%d", d.customer_code);
printf("Enter the item to edit:\n--> ");
scanf("%d", &item);
printf("\Enter your email:");
scanf("%s", &d.email);
printf("\nEnter your mobile number: ");
scanf("%lf", &d.phone);
if (main == NULL)
main = data_start(d.customer_code, d.name, d.age, d.email, d.phone, d.tin, d.country);
else
edit_data(main, item, d.customer_code, d.name, d.age, d.email, d.phone, d.tin, d.country);
}
void displays(void) {
if (!check_empty(main))
display_data(main);
}
void search(void) {
Data d;
if (!check_empty(main)) {
d.customer_code = (char *) malloc(BUFFER);
printf("Enter the name to search:\n--> ");
scanf("%d", d.customer_code);
data_search(main, d.customer_code);
}
}
void delete(void) {
if (!check_empty(main))
main = delete_data(main);
}

Answer 1

In the struct definition, nome is of type char. So scanf("%s", &d.nome); is (almost certainly) undefined behavior. nome is large enough to store a string of length zero (it can only hold the null terminator), and if there is any data for scanf to write, then the behavior is undefined since you've overflowed the buffer. If you want to store a string, you need to give it some space. Perhaps just do:
struct lista {
int *cliente_codigo;
char nome[256]; /* Make nome a character array */
int idade;
int nif;
char email;
double phone;
char pais;
struct lista *proximo;
};
and then read into it with "%255s" to ensure you don't overflow the buffer. Also, check the value returned by all your scanf and handle invalid data. (eg, discard bad input, or throw an error).
There may be other issues in your code as well, but this is certainly a show stopper.