Circular Linked List Traversal

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

/* structure for a node */
struct node
{
    int data;
    struct node *next;
};

/* Function to insert a node at the begining of a Circular
linked list */
void push(struct node **head_ref, int data)
{
    struct node *ptr1 = (struct node *)malloc(sizeof(struct node));
    struct node *temp = *head_ref;
    ptr1->data = data;
    ptr1->next = *head_ref;

    /* If linked list is not NULL then set the next of last node */
    if (*head_ref != NULL)
    {
        while (temp->next != *head_ref)
            temp = temp->next;
        temp->next = ptr1;
    }
    else
        ptr1->next = ptr1; /*For the first node */

    *head_ref = ptr1;
}

/* Function to print nodes in a given Circular linked list */
void printList(struct node *head)
{
    struct node *temp = head;
    if (head != NULL)
    {
        do
        {
            printf("%d ", temp->data);
            temp = temp->next;
        }
        while (temp != head);
    }
}

/* Driver program to test above functions */
int main()
{
    /* Initialize lists as empty */
    struct node *head = NULL;

    /* Created linked list will be 11->2->56->12 */
    push(&head, 12);
    push(&head, 56);
    push(&head, 2);
    push(&head, 11);

    printf("Contents of Circular Linked List\n ");
    printList(head);

    return 0;
}

Output:

Contents of Circular Linked List
 11 2 56 12