Insert before func.c

void insertBefore()
{
    int flagforerrormsg = 0;
    if (flagforstart == 0)
    {
        printf("\nThe Linked List is Empty. Add Elements to the Linked List use this function\n");
    }
    else
    {
        printf("\nEnter the data Before which you want to add the Node : ");
        int num;
        scanf("%d", &num);
        temp = backtemp = head;
        while (1)
        {
            if (temp->data == num)
            {
                newnode = (struct node *)malloc(sizeof(struct node));
                printf("\nEnter The Value you want to Add : ");
                scanf("%d", &newnode->data);
                newnode->next=temp;
                backtemp->next=newnode;
                break;
            }
            else if (temp->next == 0 && temp->data != num)
            {
                flagforerrormsg = 1;
                break;
            }
            else if (temp->next == 0)
            {
                break;
            }
            else
            {
                if (temp->next == head)
                {
                    temp = temp->next;
                }
                else
                {
                    temp = temp->next;
                    backtemp = backtemp->next;
                }
            }
        }
        if (flagforerrormsg == 1)
        {
            printf("\nNo element as such type a number which is there or else......\n");
        }
        else
        {
            flagforstart++;
        }
    }
}