ft_atoi_strict.c

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/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   ft_atoi_strict.c                                   :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: kfujita <kfujita@student.42tokyo.jp>       +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2023/02/12 22:16:40 by kfujita           #+#    #+#             */
/*   Updated: 2023/03/02 11:20:35 by kfujita          ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */
 
#include "../ft_is/ft_is.h"
#include "../ft_math/ft_math.h"
 
// - NULL
#include <stddef.h>
 
static bool set_value(char c, int *value, int sign)
{
    int c_value;
 
    if (!ft_isdigit(c))
        return (false);
    c_value = (c - '0') * sign;
    if (!can_mul(*value, 10) || !can_add(*value * 10, c_value))
        return (false);
    *value = (*value * 10) + c_value;
    return (true);
}
 
bool    ft_atoi_strict(const char *str, const char **endptr, int *dst)
{
    int sign;
 
    if (str == NULL || dst == NULL)
        return (false);
    if (*endptr != NULL)
        *endptr = str;
    sign = 1;
    if (*str == '-')
        sign = -1;
    if (*str == '-' || *str == '+')
        str++;
    if (*endptr != NULL)
        *endptr = str;
    if (!ft_isdigit(*str))
        return (false);
    *dst = 0;
    while (set_value(*str, dst, sign))
        str++;
    if (*endptr != NULL)
        *endptr = str;
    return (true);
}