ft_atoi.c

/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   ft_atoi.c                                          :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: achambon <marvin@42.fr>                    +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2016/11/25 14:26:32 by achambon          #+#    #+#             */
/*   Updated: 2017/01/06 14:25:23 by achambon         ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "libft.h"

int		ft_atoi(const char *str)
{
	int i;
	int result;
	int posneg;

	posneg = 1;
	i = 0;
	result = 0;
	while (ft_isspace(str[i]) == 1)
		i++;
	if (str[i] == '-' || str[i] == '+')
	{
		if (str[i] == '-')
			posneg = (-1);
		i++;
	}
	while (str[i] != '\0')
	{
		if (str[i] < '0' || str[i] > '9')
			return (result * posneg);
		result = (result * 10) + (str[i] - '0');
		i++;
	}
	return (result * posneg);
}