Doubly Linked list not working properly, C - c

Question

#include <stdio.h>
#include <stdlib.h>
typedef struct list_item {
int value;
struct list_item *next;
struct list_item *prev;
} list_item_t;
typedef struct single_list {
list_item_t *head;
list_item_t *tail;
} slist_t;
void init(slist_t *list) {
list->head = NULL;
list->tail = NULL;
}
void add(slist_t *list, int value) {
list_item_t *newNode = (list_item_t *)malloc(sizeof(list_item_t));
// Case for empty list
if (list->head == NULL) {
list->head = newNode;
list->tail = newNode;
newNode->value = value;
newNode->prev = NULL;
newNode->next = NULL;
}
// Case for nonempty list
else {
newNode->prev = list->tail;
newNode->value = value;
newNode->next = NULL;
list->tail = newNode;
}
}
void print(slist_t *list) {
if (list->head == NULL) {
printf("The list is empty\n");
return;
}
list_item_t *currentNode = list->head;
while (currentNode != NULL) {
printf("%d ", currentNode->value);
currentNode = currentNode->next;
}
printf("\n");
}
int main() {
slist_t myList;
init(&myList);
add(&myList, 5);
add(&myList, 2);
add(&myList, 6);
print(&myList);
}
Ok I got rid of my bus error but now when I try to print my list all it prints out is:
1
Is the problem in init function or my add function? I was wondering if since I don't use malloc in the init function that the list gets erased after every function call of add? Is that true? I have tried allocating it like this:
slist_t *list = (slist_t *)malloc(sizeof(slist_t))
but it gives me an error.

Answer 1

Failing to link old tail's next to the new tail.
// Case for nonempty list
else {
// Add. `list->tail->next` should be NULL before this code.
list->tail->next = newNode;
newNode->prev = list->tail;
newNode->value = value;
newNode->next = NULL;
list->tail = newNode;
}