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#include "main.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// Read a line from stdin, strip the eventual newline and return a pointer
// to the string. Remember to free the pointer.
char *read_input() {
char *buf = NULL;
size_t buf_size = 0;
size_t read = getline(&buf, &buf_size, stdin);
if (read == -1) {
free(buf);
buf = NULL;
} else if (read >= 1 && buf[read - 1] == '\n') {
buf[read - 1] = '\0';
}
return buf;
}
int read_int() {
char *buf = read_input();
int res = -1;
if (!buf) {
printf("Failed to read int from stdin\n");
} else {
res = atoi(buf);
}
free(buf);
return res;
}
// Fetch a student name from the terminal input and add it to the list.
void insert(struct list *student_list) {
struct student *student = malloc(sizeof(struct student));
char *name = read_input();
if (!name) {
printf("Failed to read student name\n");
free(student);
} else {
student->name = name;
printf("Inserted student with name '%s'\n", student->name);
list_push_front(student_list, &student->elem);
}
}
// Get a student name from the terminal input, remove it from the list and
// deallocate the appropriate memory (if needed).
void delete(struct list *student_list) {
char *name = read_input();
if (!name) {
printf("Failed to read student name\n");
} else {
struct list_elem *e;
for (e = list_begin(student_list); e != list_end(student_list);
e = list_next(e))
{
struct student *student = list_entry(e, struct student, elem);
if (strcmp(student->name, name) == 0) {
printf("Removing student '%s'\n", student->name);
list_remove(&student->elem);
free(student->name);
free(student);
break;
}
}
}
free(name);
}
// Print the entire list.
void list(struct list *student_list) {
struct list_elem *e;
for (e = list_begin(student_list); e != list_end(student_list);
e = list_next(e))
{
struct student *student = list_entry(e, struct student, elem);
printf("Student: %s\n", student->name);
}
}
// Clear the list and deallocate the memory.
void quit(struct list *student_list) {
struct list_elem *e;
struct student *student;
while (!list_empty(student_list)) {
e = list_pop_front(student_list);
student = list_entry(e, struct student, elem);
printf("Removing '%s'\n", student->name);
free(student->name);
free(student);
}
exit(0);
}
int main() {
struct list student_list;
list_init(&student_list);
int opt;
do {
printf("Menu:\n");
printf("1 - Insert student\n");
printf("2 - Delete student\n");
printf("3 - List students\n");
printf("4 - Exit\n");
switch (read_int()) {
case 1:
{
insert(&student_list);
break;
}
case 2:
{
delete(&student_list);
break;
}
case 3:
{
list(&student_list);
break;
}
case 4:
{
quit(&student_list);
break;
}
default:
{
printf("Quit? (1/0):\n");
if (read_int())
quit(&student_list);
break;
}
}
} while(1);
return 0;
}
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