linked_list_reverse.c

#include <stdlib.h>

struct node {
    int data;
    struct node* next;
};

static void reverse(struct node** head_ref) {
    struct node* tmp_prev = NULL;
    struct node* current = *head_ref;
    struct node* tmp_next;

    while (current != NULL) {
       tmp_next = current->next;
       current->next = tmp_prev;
       tmp_prev = current;
       current = tmp_next;
    }

    *head_ref = tmp_prev;
}


int main(void) {
    int i;

    struct node *hn_ptr = NULL;
    struct node *pn_ptr = NULL;
    struct node *n_ptr = NULL;

    for (i = 0; i < 10; i++) {
        n_ptr = malloc(sizeof(struct node) * 1);

        if (!n_ptr)
            return EXIT_FAILURE;

        n_ptr->data = i;

        if (pn_ptr != NULL)
            pn_ptr->next = n_ptr;

        pn_ptr = n_ptr;

        if (i == 0)
            hn_ptr = n_ptr;
    }

    reverse(&hn_ptr);

    return EXIT_SUCCESS;
}