stack_operations.c

#include "monty.h"

/**
 * add_to_stack - Adds a node to the stack.
 * @new_node: Pointer to the new node.
 * @ln: Interger representing the line number of of the opcode.
 */

void add_to_stack(stack_t **new_node, __attribute__((unused))unsigned int ln)
{
	stack_t *tmp;

	if (new_node == NULL || *new_node == NULL)
		exit(EXIT_FAILURE);
	if (head == NULL)
	{
		head = *new_node;
		return;
	}
	tmp = head;
	head = *new_node;
	head->next = tmp;
	tmp->prev = head;
}

/**
 * pop - pop the item from the top of stack.
 *
 * @stack: stack pointer.
 * @line_number: line number that called this funciton.
 */

void pop(stack_t **stack, unsigned int line_number)
{
	stack_t *tmp;

	if (*stack == NULL)
		error(7, line_number);
	else
	{
		tmp = *stack;
		*stack = tmp->next;
		free(tmp);
	}
}