linkedlist.c

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

typedef struct node {
    int value;
    struct node * next;
} node_t;

node_t * node_new(void) {
    node_t * new_node = NULL;
    new_node = malloc(sizeof(node_t));

    if (new_node == NULL) {
        printf("could not allocate for node\n");
        return NULL;
    }
    
    new_node->value = -1;
    new_node->next = NULL;
    return new_node;
}

node_t * list_new(void) {
    node_t * head = node_new();
    return head;
}

void list_add(node_t * list, int value) {
    if (list->value == -1) {
        list->value = value;
        return;
    }

    node_t * new_node = node_new();
    new_node->value = value;

    // navigate to the last node
    node_t * current_node = list;
    if (current_node->next != NULL) {
        while (current_node->next != NULL) {
            current_node = current_node->next;
        }
    }

    current_node->next = new_node;
}

void list_print(node_t * list) {
    node_t * current_node = list;
    while (current_node->next != NULL) {
        printf("%d\n", current_node->value);
        current_node = current_node->next;
    }
    printf("%d\n", current_node->value);
}

void list_cleanup(node_t * list) {
    if (list == NULL) {
        return;
    }

    list_cleanup(list->next);

    free(list);
}

int main(void) {
    node_t * list = list_new();

    list_add(list, 5);
    list_add(list, 95);
    list_add(list, 134);

    list_print(list);
    list_cleanup(list);
    
    return 0;
}